TWI847106B - Manufacturing method of anisotropic conductive film - Google Patents

Abstract

The invention relates to a manufacturing method of anisotropic conductive film. In particular, the manufacturing method uses a magnetic attraction device to generate a magnetic force to attract the conductive core of the conductive particles, so that the conductive particles are adsorbed on the transfer surface of the transfer substrate after leaving the accommodating groove. Realize the transfer of conductive particles without contacting the wafer to form a continuous anisotropic conductive adhesive, which is very suitable for mass production.

Description

Method for preparing anisotropic conductive glue

The present invention relates to a method for manufacturing anisotropic conductive glue, in particular, utilizing a plurality of array-arranged receiving grooves on a wafer for receiving conductive particles in the receiving grooves, and at the same time, using a magnetic attraction device to generate a magnetic force to attract the conductive core of the conductive particles, and transferring the conductive particles without contacting the wafer, thereby achieving the purpose of placing the conductive particles according to the arrangement of the receiving grooves to manufacture a continuous anisotropic conductive glue.

With the advancement of the electronics industry and semiconductor technology, many terminal electronic products have not only become more powerful in terms of functionality, but also have been continuously pursuing lighter, thinner, shorter and smaller appearances to improve practicality.

For example, traditional monitors using cathode ray tubes not only take up too much valuable desktop space, but are also quite bulky and consume too much power, especially for large-sized monitors. In recent years, liquid crystal displays (LCDs) made using advanced electronic and semiconductor technologies have been able to significantly reduce weight and overall size, thus almost completely replacing cathode ray tube monitors.

Take smartphones as an example. They are not only portable and have the functions of making calls and sending text messages, but also can take pictures and play high-definition videos. At the same time, they are highly power-saving and can greatly extend the battery life. Now, almost everyone has one, and they can be said to be the most successful consumer electronic product.

The above-mentioned electronic products all require that different electronic components be electrically connected to the electronic circuits on the circuit board. Traditionally, the process of using solder to achieve the purpose of welding cannot meet the requirements of lightness, thinness, shortness and smallness even if lead-tin alloy solder with low-temperature melting characteristics and better conductivity is used, especially for electronic components of integrated circuits (ICs) whose sizes have been greatly reduced. Although the technology of surface mount devices (SMD) can solve the challenge of size reduction, it requires the use of high-temperature furnaces to accelerate the welding process and thus increase production, which will produce potential damage risks to electronic components.

Therefore, the industry has developed anisotropic conductive film (ACF) for use in the manufacturing process of chip on glass (COG) or chip on film (COF). ACF is used to achieve electrical connection in a specific direction, such as being conductive in the vertical direction but not conductive in the horizontal direction. For example, it can be used to connect the pins of the driver IC to each pixel of the panel to meet the fine pitch requirements of the display panel.

In short, anisotropic conductive film is composed of resin and conductive particles (or conductive powder), which can be used to connect two different substrates and circuits. In addition, anisotropic conductive film has the characteristics of vertical (Z-axis) electrical conductivity and horizontal (X, Y-axis) insulation. It can usually be heated and treated with external pressure in the Z-axis direction to make the separated conductive particles contained in it contact with each other to achieve the purpose of electrical conductivity in the Z-axis direction and electrical insulation in the plane direction at the same time, thereby avoiding short circuits between adjacent pins.

In the conventional technology of making anisotropic conductive film, a plurality of conductive particles need to be embedded in a non-conductive gel film, and each conductive particle includes an insulating film and a conductive core body, wherein the insulating film covers the outer surface of the conductive core body. When in use, the electronic components or circuits to be connected are placed on the upper and lower sides of the anisotropic conductive film, and then the anisotropic conductive film is squeezed by applying external forces from top to bottom, so that the insulating film of the anisotropic conductive film is broken to expose the coated conductive core body, so that the electronic components or circuits can achieve electrical conduction by contacting the conductive core body. Since adjacent conductive particles can be arranged very close, the requirements of fine spacing can be met.

Furthermore, to embed multiple conductive particles in a non-conductive adhesive film and arrange them in an appropriately dispersed manner, a transfer technique is generally used. For example, the conductive particles are first placed on a configuration plate or a configuration film, and the configuration plate or the configuration film has multiple recesses in a specific arrangement to accommodate the conductive particles. Then, a non-conductive adhesive film is attached to cover the conductive particles, and the configuration plate or the configuration film is removed. Finally, a second non-conductive adhesive film is attached to cover the conductive particles, thereby embedding all the conductive particles.

However, the disadvantage of the prior art is that the adhesion of the concave holes of the configuration plate or configuration film to the conductive particles is difficult to control, resulting in that when the configuration plate or configuration film is removed, some of the conductive particles are still attached to the configuration plate or configuration film, and are not transferred to the non-conductive adhesive film, affecting the overall electrical connection function of the anisotropic conductive adhesive. In addition, the configuration plate or configuration film of the prior art generally transfers the conductive particles by contact, resulting in residual adhesive residues on the configuration plate or configuration film, making the quality of the anisotropic conductive adhesive poor, and the configuration plate or configuration film must be frequently replaced or cleaned, resulting in increased costs and great inconvenience.

In view of the above shortcomings, the inventor has studied ways to improve these shortcomings and finally came up with the present invention.

The main purpose of the present invention is to provide a method for manufacturing anisotropic conductive adhesive, which is to provide a plurality of receiving grooves on a wafer, and the receiving grooves are arranged in an array, so that adjacent conductive particles are arranged very close to each other to meet the requirements of fine spacing. In addition, a magnetic attraction device is used to generate a magnetic force to attract the conductive core of the conductive particles, so that the conductive particles are adsorbed on the transfer surface of the transfer substrate after leaving the receiving grooves, so that the conductive particles are transferred without contacting the wafer, forming a continuous anisotropic conductive adhesive, which is very suitable for mass production, and at the same time solves the problem of residual adhesive easily remaining on the configuration plate or configuration film, thereby reducing costs and increasing production.

In order to achieve the above-mentioned purpose and effect, the present invention provides a method for manufacturing anisotropic conductive glue, which includes: an arrangement preparation step, which is to place a wafer in a transmission device, wherein a plurality of receiving slots are arranged in an array, and the transmission device includes a plurality of rollers and a driver, wherein the rollers are connected to the driver and are driven by the driver to roll in a forward direction and drive the wafer to move in the forward direction; a conductive particle sprinkling step, which is to spread or spray a plurality of conductive particles on the wafer, wherein each of the receiving slots can accommodate at most a single conductive particle, wherein wherein each of the conductive particles has an outer diameter and includes an insulating film and a conductive core body; a step of removing excess conductive particles, using a particle removal device to remove excess conductive particles not contained in the containing groove; a magnetic attraction step, wherein the wafer is moved to a position parallel to a transfer substrate, the transfer substrate is coupled to a magnetic attraction device, the magnetic attraction device generates a magnetic force to attract the conductive core body of the conductive particles, so that the conductive particles leave the containing grooves and are adsorbed on a transfer surface of the transfer substrate; a transfer step, wherein a first non-conductive adhesive film (Non-Conductive The invention discloses a method for preparing a non-conductive adhesive film and a method for preparing a non-conductive adhesive film. The method comprises the steps of: moving a non-conductive adhesive film (NCF) to a position parallel to the transfer substrate, and releasing the magnetic force of the magnetic attraction device; a separation step, separating the conductive particles from the transfer substrate, and leaving the conductive particles on a pair of pasting surfaces of the first non-conductive adhesive film; and a pair of pasting modules, pasting a second non-conductive adhesive film on the pair of pasting surfaces of the first non-conductive adhesive film to cover the conductive particles and form a continuous anisotropic conductive adhesive.

Preferably, according to the method for manufacturing anisotropic conductive adhesive of the present invention, the transfer surface of the transfer substrate is sticky, and the sticking surface of the first non-conductive adhesive film has a greater stickiness than the transfer surface.

Preferably, according to the method for making anisotropic conductive adhesive of the present invention, the method for making anisotropic conductive adhesive further comprises: an attaching step, attaching the first non-conductive adhesive film to the transfer substrate, and the first non-conductive adhesive film is attached to the conductive particles remaining on the transfer surface by contact; wherein the separating step further separates the transfer substrate from the first non-conductive adhesive film by peeling, and since the viscosity of the first non-conductive adhesive film is greater than the viscosity of the transfer surface, the conductive particles remain on the first non-conductive adhesive film.

Preferably, according to the method for making anisotropic conductive adhesive of the present invention, the transfer surface comprises a medium-viscosity film, the medium-viscosity film itself has viscosity, and the viscosity of the medium-viscosity film is between 40% and 80% of the viscosity of the first non-conductive adhesive film. The medium-viscosity film is adhered to the counter-attaching surface of the first non-conductive adhesive film in the attaching step, and the counter-attaching surface covers and contacts the conductive particles. Then, the conductive adhesive film is peeled off and separated from the medium-viscosity film, and the conductive particles remain on the counter-attaching surface of the conductive adhesive film.

Preferably, according to the method for making anisotropic conductive adhesive of the present invention, the transfer substrate is made of a non-metallic material, and the non-metallic material is selected from one of polycarbonate, polyethylene terephthalate, polymethyl methacrylate, polyimide, and polyethylene naphthalate.

Preferably, according to the method for manufacturing anisotropic conductive paste of the present invention, the transfer substrate is made of a metal material, and the metal material is selected from one of nickel, copper, aluminum, and zinc.

Preferably, according to the method for making anisotropic conductive adhesive of the present invention, the receiving grooves have a width ranging from 1.1 times to 1.9 times the diameter of the conductive particles.

Preferably, according to the method for making anisotropic conductive paste of the present invention, the receiving grooves have a depth ranging from 0.5 times to 1.1 times the diameter of the conductive particles.

Preferably, according to the method for manufacturing anisotropic conductive adhesive of the present invention, the driver includes at least one electric motor.

Preferably, according to the method for manufacturing anisotropic conductive adhesive of the present invention, the second non-conductive adhesive film and the first non-conductive adhesive film are made of the same material, which is selected from one of polyurethane (PU) and epoxy resin.

In order to enable persons familiar with the art to understand the purpose, features and effects of the present invention, the present invention is described in detail as follows through the following specific embodiments and in conjunction with the attached drawings.

The inventive concept will now be more fully explained below with reference to the accompanying drawings in which exemplary embodiments of the inventive concept are shown. Advantages and features of the inventive concept and methods of achieving the same will become apparent from the exemplary embodiments explained in more detail below with reference to the accompanying drawings. However, it should be noted that the inventive concept is not limited to the following exemplary embodiments, but can be implemented in various forms. Therefore, the exemplary embodiments are provided only to disclose the inventive concept and to enable those skilled in the art to understand the category of the inventive concept. In the drawings, the exemplary embodiments of the inventive concept are not limited to the specific examples provided herein and are exaggerated for clarity.

The terms used herein are used only to describe specific embodiments and are not intended to limit the present invention. Unless the context clearly indicates otherwise, the singular forms of the terms "a", "an" and "the" used herein are intended to include the plural forms as well. The term "and/or" used herein includes any and all combinations of one or more of the relevant listed items. It should be understood that when an element is said to be "connected" or "coupled" to another element, the element may be directly connected or coupled to the other element or there may be intermediate elements.

Similarly, it should be understood that when an element (such as a layer, region, or substrate) is said to be "on" another element, the element may be directly on the other element, or there may be intervening elements. In contrast, the term "directly" means that there are no intervening elements. It should be further understood that when the terms "include" and "comprising" are used herein, they indicate the presence of the stated features, integers, steps, operations, elements, and/or components, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof.

Furthermore, exemplary embodiments in the detailed description will be illustrated by cross-sectional views that are idealized exemplary views of the inventive concept. Accordingly, the shapes of the exemplary views may be modified according to manufacturing techniques and/or tolerable errors. Therefore, exemplary embodiments of the inventive concept are not limited to the specific shapes shown in the exemplary views, but may include other shapes that may be produced according to the manufacturing process. The areas illustrated in the drawings are of general nature and are used to illustrate specific shapes of the elements. Therefore, this should not be considered as limiting the scope of the inventive concept.

It should also be understood that although the terms "first", "second", "third", etc. may be used herein to describe various elements, these elements should not be limited to these terms. These terms are only used to distinguish between various elements. Therefore, the first element in some embodiments may be referred to as the second element in other embodiments without departing from the teachings of the present invention. The exemplary embodiments of the aspects of the inventive concept explained and illustrated herein include their complementary counterparts. Throughout this specification, the same reference numerals or the same indicators represent the same elements.

Furthermore, exemplary embodiments are described herein with reference to cross-sectional views and/or plan views, wherein the cross-sectional views and/or plan views are idealized exemplary illustrations. Therefore, deviations from the illustrated shapes due to, for example, manufacturing techniques and/or tolerances are expected. Therefore, the exemplary embodiments should not be considered limited to the shapes of the regions shown herein, but are intended to include shape deviations due to, for example, manufacturing. Therefore, the regions shown in the figures are schematic, and their shapes are not intended to illustrate the actual shapes of the regions of the device, nor are they intended to limit the scope of the exemplary embodiments.

Please refer to FIG. 1 to FIG. 2B , FIG. 1 is a process flow diagram of the method for making anisotropic conductive glue according to the present invention; FIG. 2A-2B are system diagrams of the method for making anisotropic conductive glue according to the present invention. As shown in FIG. 1 to FIG. 2A-2B , the method for making anisotropic conductive glue according to the present invention includes: an arrangement preparation step S10, a conductive particle sprinkling step S20, a step of removing excess conductive particles S30, a magnetic attraction step S40, a transfer step S50, a separation step S60, and a bonding step S70, for making a continuous anisotropic conductive glue, which is convenient for mass production and can control quality.

Specifically, the manufacturing method of the anisotropic conductive adhesive of the present invention starts with an arrangement preparation step S10, which mainly includes placing a wafer 10 in a transmission device 20. A receiving groove 11 is provided on the wafer 10. The transmission device 20 includes a plurality of rollers 21 and a driver 22. The rollers 21 are connected to the driver 22, such as by a chain, a gear set or a transmission rod, and the rollers 21 are driven by the driver 22 to roll in a forward direction D and drive the wafer 10 to move in the forward direction D, so as to continuously feed the wafer 10 for subsequent processing. For example, the driver 22 may include at least one electric motor.

Specifically, as shown in FIG3 and FIG4, FIG3 is a schematic diagram of a wafer according to the method for making anisotropic conductive paste of the present invention; FIG4 is another schematic diagram of a wafer according to the method for making anisotropic conductive paste of the present invention. In some embodiments, the receiving grooves 11 are specially configured to be separated without contacting each other, and preferably, the receiving grooves 11 are distributed in an array. In addition, each receiving groove 11 can be in the shape of a dot and have a specific area size. It should be noted that in the array arrangement, the lateral distance between two adjacent accommodating grooves 11 in the horizontal direction may be the same as or different from the vertical distance between two adjacent accommodating grooves 11 in the vertical direction, that is, the lateral distance and the vertical distance may be designed separately according to actual needs.

Specifically, as shown in FIG. 3 and FIG. 4 , in some embodiments, the receiving groove 11 of the wafer 10 has a width W, and the width W is between 1.1 times and 1.9 times the diameter of the conductive particle 30. Preferably, the width W is between 1.3 times and 1.8 times the diameter of the conductive particle 30. In some embodiments, the receiving groove 11 of the wafer 10 has a depth h, and the depth h is between 0.5 times and 1.1 times the diameter of the conductive particle 30. Preferably, the depth h is between 0.5 times and 1.1 times the diameter of the conductive particle 30. In this way, the wafer 10 of the present invention adjusts the size of the receiving groove to prevent the receiving groove from repeatedly accommodating excess conductive particles 30, so as to ensure that the excess conductive particles 30 are removed in the subsequent excess conductive particle removal step S30, thereby improving the quality of the continuous anisotropic conductive adhesive produced by the manufacturing method of the anisotropic conductive adhesive of the present invention, and is easy to implement and very suitable for mass production.

Next, in the conductive particle spraying step S20 , a plurality of conductive particles 30 are sprayed or laid on the wafer 10 , for example, by a particle sprayer 40 , and some of the conductive particles 30 are accommodated in the receiving grooves 11 . In particular, the receiving groove 11 can accommodate only a single conductive particle 30 at most.

The structure of the conductive particles 30 is a common known technology and is not the focus of the present invention, so it is only briefly described here. Each conductive particle 30 has an outer diameter and includes an insulating film (not shown) and a conductive core (not shown), wherein the insulating film covers the outer surface of the conductive core. In particular, the insulating film is configured to rupture under the pressure of an external force to expose the coated conductive core, so that electrical conduction is formed in the direction of the external force due to the contact of the conductive core, thereby achieving the purpose of conduction.

It should be further explained that, as shown in FIG. 3 , although the receiving grooves 11 are configured to be separated without contact with each other, in order to avoid the conductive particles 30 being overly densely packed on the receiving grooves 11 and causing two adjacent conductive particles 30 to affect each other, the lateral spacing and vertical spacing of the receiving grooves 11 in the wafer 10 are specially configured so that the spacing L between two adjacent receiving grooves 11 in the receiving grooves 11 can be greater than 10% to 200% of the outer diameter of the conductive particle 30.

Then, the step S30 of removing excess conductive particles is performed, and the excess conductive particles 30 not contained in the containing grooves 11 are removed by using the particle removing device 50. That is, only the conductive particles 30 contained in the containing grooves 11 remain on the wafer 10.

For example, the particle removal device 50 may include a brush or a blower, and the figure uses a brush as an exemplary example. In essence, the brush removes the excess conductive particles 30 by scraping, and the blower blows away the excess conductive particles 30 by blowing, such as using a blower to generate a jet of air, but the present invention is not limited thereto.

In the magnetic attraction step S40, the wafer 10 is moved to a position parallel to the transfer substrate 60. The transfer substrate 60 is coupled to a magnetic attraction device 70. The magnetic attraction device 70 generates a magnetic force F to attract the conductive cores of the conductive particles 30, so that the conductive particles 30 leave the accommodating groove 11 and are adsorbed on the transfer surface 61 of the transfer substrate 60.

Specifically, in some embodiments, the transfer substrate 60 is made of a non-metallic material, and the non-metallic material is selected from one of polycarbonate, polyethylene terephthalate, polymethyl methacrylate, polyimide, and polyethylene naphthalate. The above-mentioned non-metallic material has stable chemical properties, good elasticity, and ductility, so that the transfer substrate 60 can be arranged in the form of a tape or a reel so that it can be continuously pulled out and fed in for subsequent processing, and has wide applicability. Specifically, in some embodiments, the transfer substrate 60 is made of a metal material, and the metal material is selected from one of nickel, copper, aluminum, and zinc. The above metal materials all have high magnetic permeability. Under the action of an external magnetic field, the internal magnetic induction intensity will be greatly enhanced, so that the magnetic force F generated by the magnetic attraction device 70 can be effectively transmitted to the conductive particles 30, stably attracting the conductive core bodies of the conductive particles 30, and preventing the risk of the conductive particles 30 falling, thereby further ensuring the quality of the continuous anisotropic conductive glue made by the present invention, but the present invention is not limited to this.

Specifically, the magnetic attraction device 70 may be a device having an electromagnet, wherein the electromagnet is a device that can generate a magnetic force F through an electric current, so as to control the generation of the magnetic force F through the electric current. It should be further explained that the magnitude of the magnetic force F generated by the magnetic attraction device 70 is related to the transfer substrate 60. It can be understood that when the transfer substrate 60 is made of non-metallic material, since the non-metallic material is a non-magnetic material, the magnetic attraction device 70 must generate a stronger magnetic force F to attract the conductive core body of the conductive particles 30. The magnetic force F may be between 20,000 Gauss (Gs) and 30,000 Gauss. On the contrary, when the transfer substrate 60 is made of metal material, since the metal material has better magnetic permeability, the magnetic attraction device 70 can generate a weaker magnetic force F to attract the conductive core body of the conductive particles 30. The magnetic force F can be between 5000 Gauss and 20,000 Gauss. Preferably, the magnetic force F can be between 10,000 Gauss and 20,000 Gauss, but the present invention is not limited to this.

In the transfer step S50 , the first non-conductive film (NCF) 81 is moved to a position parallel to the transfer substrate 60 via the transmission device 20 , and the magnetic attraction device 70 releases the magnetic force F.

For example, the first non-conductive adhesive film 81 may be made of a non-metallic material, such as polyurethane (PU) or epoxy resin.

Then, the separation step S60 is entered, the conductive particles 30 and the transfer substrate 60 are separated from each other, and the conductive particles 30 remain on the facing surface 811 of the first non-conductive adhesive film 81. Specifically, in some embodiments, the facing surface 811 of the first non-conductive adhesive film 81 may be adhesive, so that the conductive particles 30 are fixed on the facing surface 811 of the first non-conductive adhesive film 81, but the present invention is not limited thereto.

In addition, since the transfer substrate 60 is arranged parallel to the first non-conductive adhesive film 81 during the transfer step S50, after entering the separation step S60, when the conductive particles 30 are separated from the transfer substrate 60 and fall onto the first non-conductive adhesive film 81, the arrangement of the conductive particles 30 on the first non-conductive adhesive film 81 will be consistent with the arrangement of the receiving grooves 11 of the wafer 10. In this way, the user can control the arrangement of the conductive particles 30 on the first non-conductive adhesive film 81 by adjusting the arrangement of the receiving grooves 11 of the wafer 10, thereby arranging the conductive particles 30 in a preset specific pattern without having to manually adjust the arrangement of the conductive particles 30 on the first non-conductive adhesive film 81. This is very suitable for mass production and ensures stable quality, which cannot be achieved by ordinary batch production methods.

Finally, in the laminating step S60, the second non-conductive adhesive film 82 is attached to the first non-conductive adhesive film 81 to cover the conductive particles 30, forming the desired continuous anisotropic conductive adhesive 90, wherein the conductive particles 30 are sandwiched by the second non-conductive adhesive film 82 and the first non-conductive adhesive film 81 to form a single-layer distribution configuration. Specifically, the second non-conductive adhesive film 82 and the first non-conductive adhesive film 81 can be made of the same material, but the present invention is not limited thereto.

Since the transfer substrate 60, the first non-conductive adhesive film 81 and the second non-conductive adhesive film 82 can be arranged in the form of a tape or a reel so as to be continuously pulled out and fed in for subsequent processing, a continuous anisotropic conductive adhesive 90 can be continuously produced, which is very suitable for mass production and ensures stable quality, which cannot be achieved by a general batch production method.

In general, the present invention arranges the receiving groove 11 on the wafer 10 and uses magnetic attraction to arrange all the conductive particles 30 at specific positions of the first non-conductive adhesive film 81 and sandwiched between the first non-conductive adhesive film 81 and the second non-conductive adhesive film 82, so as to achieve the purpose of accurately and strictly controlling the arrangement position of the conductive particles 30 of the anisotropic conductive adhesive 90.

Other examples of methods for making anisotropic conductive adhesive are provided below so that those skilled in the art can more clearly understand possible variations. Elements indicated by the same element symbols as in the above-mentioned embodiments are substantially the same as those described above with reference to FIGS. 1 to 2B. The same elements, features, and advantages as in the previous methods for making anisotropic conductive adhesive will not be described in detail.

Please refer to FIG. 5 to FIG. 6B , FIG. 5 is a process flow diagram of a method for making anisotropic conductive glue according to another embodiment of the present invention; FIG. 6A-6B are system diagrams of a method for making anisotropic conductive glue according to another embodiment of the present invention. As shown in FIG. 5 and FIG. 6B , the method for making anisotropic conductive glue according to another embodiment of the present invention includes: an arrangement preparation step S10 ', a conductive particle sprinkling step S20 ', a step of removing excess conductive particles S30 ', a magnetic attraction step S40 ', a transfer step S50 ', a pasting step S60 ', a separation step S70 ', and a pasting step S80 '.

Specifically, in this embodiment, since the transfer surface 61 of the transfer substrate 60 is sticky, after the magnetic attraction device 70 releases the magnetic force F in the transfer step S50', the conductive particles 30 will be fixed on the transfer surface 61 to reduce the risk of the conductive particles 30 falling. Specifically, the transfer surface 61 may include a medium-viscosity film (not shown), which is sticky and has a viscosity between 40% and 80% of the original viscosity of the first non-conductive adhesive film 81, that is, the viscosity of the counter-attachment surface 811 of the first non-conductive adhesive film 81 is greater than the viscosity of the transfer surface 61.

In the attaching step S60', the first non-conductive adhesive film 81 is attached to the transfer surface 61 of the transfer substrate 60, and the first non-conductive adhesive film 81 is attached to the conductive particles 30 remaining on the transfer surface 61 by contact. It should be further explained that, since the transfer surface 61 of the transfer substrate 60 is sticky, the conductive particles 30 cannot be separated from the transfer surface 61 simply by removing the magnetic force F. In this embodiment, the stickiness of the counter-attachment surface 811 of the first non-conductive adhesive film 81 is greater than the stickiness of the transfer surface 61, and the conductive particles 30 remaining on the transfer surface 61 are attached by contact.

In this embodiment, the separation step S70 ′ further separates the transfer substrate 60 from the first non-conductive adhesive film 81 by peeling. Since the viscosity of the first non-conductive adhesive film 81 is greater than the viscosity of the transfer surface 61 , the conductive particles 30 remain on the first non-conductive adhesive film 81 .

Specifically, in actual operation, the counter-attachment surface 811 of the first non-conductive adhesive film 81 is first attached to the transfer surface 61 to cover and contact the conductive particles 30, and then the first non-conductive adhesive film 81 is peeled off to separate from the transfer surface 61. Obviously, since the adhesion of the transfer surface 61 to the conductive particles 30 is 40% to 80% of that of the first non-conductive adhesive film 81, the conductive particles 30 adhered to both the first non-conductive adhesive film 81 and the transfer surface 61 will remain on the counter-attachment surface 811 of the first non-conductive adhesive film 81 when the transfer substrate 60 and the conductive adhesive film 81 are peeled off from each other, and will not remain on the transfer surface 61.

It is understandable that a person having ordinary knowledge in the technical field to which the present invention belongs can make various changes and adjustments based on the above examples, which will not be listed one by one here.

The above is an explanation of the implementation of the present invention by means of specific embodiments. A person having ordinary knowledge in the relevant technical field can easily understand other advantages and effects of the present invention from the contents disclosed in this specification.

The above description is only a preferred embodiment of the present invention and is not intended to limit the scope of the present invention; any other equivalent changes or modifications that are accomplished without departing from the spirit disclosed by the present invention should be included in the following patent scope.

10: Wafer 11: Receiving slot 20: Conveying device 21: Roller 22: Driver 30: Conductive particles 40: Particle sprayer 50: Particle removal device 60: Transfer substrate 61: Transfer surface 70: Magnetic device 81: First non-conductive adhesive film 82: Second non-conductive adhesive film 811: Attachment surface 90: Anisotropic conductive adhesive D: Forward direction F: Magnetic force h: Depth W: Width L: Spacing S10: Arrangement preparation step S20: Conductive particle spraying step S30: Removal of excess conductive particles step S40: Magnetic attraction step S50: Transfer step S60: Separation step S70: Attachment step S10': Arrangement preparation step S20': Sprinkling conductive particles step S30': Removing excess conductive particles step S40': Magnetic attraction step S50': Transfer step S60': Attachment step S70': Separation step S80': Attachment step

FIG1 is a schematic diagram of a processing flow of a method for making anisotropic conductive glue according to the present invention; FIG2A-2B are schematic diagrams of a system of a method for making anisotropic conductive glue according to the present invention; FIG3 is a schematic diagram of a wafer of a method for making anisotropic conductive glue according to the present invention; FIG4 is another schematic diagram of a wafer of a method for making anisotropic conductive glue according to the present invention; FIG5 is a schematic diagram of a processing flow of a method for making anisotropic conductive glue according to another embodiment of the present invention; FIG6A-6B are schematic diagrams of a system of a method for making anisotropic conductive glue according to another embodiment of the present invention.

S10: Arrange preparation steps

S20: Step of sprinkling conductive particles

S30: Step of removing excess conductive particles

S40: Magnetic suction step

S50: Transfer step

S60: Separation step

S70: Pasting steps

Claims (10)

A method for making anisotropic conductive glue includes: An arrangement preparation step, which is to place a wafer in a transmission device, the wafer is provided with a plurality of receiving slots, and the receiving slots are arranged in an array, the transmission device includes a plurality of rollers and a driver, the rollers are connected to the driver, and are driven by the driver to roll in a forward direction, and drive the wafer to move in the forward direction; A step of sprinkling conductive particles, laying or spraying a plurality of conductive particles on the wafer, and each of the containing grooves can only contain a single conductive particle at most, wherein each of the conductive particles has an outer diameter and includes an insulating film and a conductive core body, and the insulating film covers the outer surface of the conductive core body; A step of removing excess conductive particles, using a particle removal device to remove the excess conductive particles not contained in the containing groove; A magnetic attraction step, the wafer moves to a position parallel to a transfer substrate, the transfer substrate is coupled to a magnetic attraction device, and the magnetic attraction device generates a magnetic force to attract the conductive core body of the conductive particles, so that the conductive particles leave the containing grooves and are adsorbed on a transfer surface of the transfer substrate; A transfer step, a first non-conductive film (NCF) moves to a position parallel to the transfer substrate, and the magnetic attraction device releases the magnetic force; A separation step, the conductive particles are separated from the transfer substrate, and the conductive particles remain on a pair of pasting surfaces of the first non-conductive film; A pair pasting step, a second non-conductive film is pasted on the pair of pasting surfaces of the first non-conductive film to cover the conductive particles to form a continuous anisotropic conductive adhesive. The method for manufacturing anisotropic conductive adhesive as described in claim 1, wherein the transfer surface of the transfer substrate is sticky, and the stickiness of the opposing surface of the first non-conductive adhesive film is greater than the stickiness of the transfer surface. The method for making anisotropic conductive adhesive as described in claim 2, wherein the method for making anisotropic conductive adhesive further comprises: an attaching step, attaching the first non-conductive adhesive film to the transfer substrate, and the first non-conductive adhesive film is attached to the conductive particles remaining on the transfer surface by contact; wherein the separation step further separates the transfer substrate from the first non-conductive adhesive film by peeling, and since the viscosity of the first non-conductive adhesive film is greater than the viscosity of the transfer surface, the conductive particles remain on the first non-conductive adhesive film. A method for making anisotropic conductive adhesive as described in claim 2, wherein the transfer surface includes a medium-viscosity film, the medium-viscosity film itself is sticky, and the viscosity of the medium-viscosity film is between 40% and 80% of the viscosity of the first non-conductive adhesive film. The medium-viscosity film is adhered to the counter-attachment surface of the first non-conductive adhesive film during the attachment step, and the counter-attachment surface covers and contacts the conductive particles. The conductive adhesive film is then peeled off and separated from the medium-viscosity film, and the conductive particles remain on the counter-attachment surface of the conductive adhesive film. A method for producing anisotropic conductive adhesive as described in claim 1, wherein the transfer substrate is made of a non-metallic material, and the non-metallic material is selected from one of polycarbonate, polyethylene terephthalate, polymethyl methacrylate, polyimide, and polyethylene naphthalate. The method for manufacturing anisotropic conductive paste as described in claim 1, wherein the transfer substrate is made of a metal material, and the metal material is selected from one of nickel, copper, aluminum, and zinc. A method for manufacturing anisotropic conductive adhesive as described in claim 1, wherein the receiving grooves have a width ranging from 1.1 times to 1.9 times the diameter of the conductive particles. A method for manufacturing anisotropic conductive paste as described in claim 1, wherein the receiving grooves have a depth ranging from 0.5 times to 1.1 times the diameter of the conductive particles. A method for manufacturing anisotropic conductive adhesive as described in claim 1, wherein the driver includes at least one electric motor. The method for manufacturing anisotropic conductive adhesive as claimed in claim 1, wherein the second non-conductive adhesive film and the first non-conductive adhesive film are made of the same material, which is selected from one of polyurethane (PU) and epoxy resin.

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