CN110769674B - Electromagnetic shielding film, circuit board and preparation method of electromagnetic shielding film - Google Patents
Electromagnetic shielding film, circuit board and preparation method of electromagnetic shielding film Download PDFInfo
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Classifications
-
- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
- H05K9/00—Screening of apparatus or components against electric or magnetic fields
- H05K9/0073—Shielding materials
- H05K9/0081—Electromagnetic shielding materials, e.g. EMI, RFI shielding
- H05K9/0088—Electromagnetic shielding materials, e.g. EMI, RFI shielding comprising a plurality of shielding layers; combining different shielding material structure
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- Electromagnetism (AREA)
- Engineering & Computer Science (AREA)
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- Shielding Devices Or Components To Electric Or Magnetic Fields (AREA)
Abstract
The invention relates to the technical field of electronics and discloses an electromagnetic shielding film, a circuit board and a preparation method of the electromagnetic shielding film, wherein the electromagnetic shielding film comprises a first shielding layer, an insulating layer, a second shielding layer and a glue film layer which are sequentially stacked, the insulating layer is provided with holes, the first shielding layer and the second shielding layer are in mutual contact through the holes to realize electric conduction, one surface of the second shielding layer, which is close to the glue film layer, is a flat surface, and one surface of the second shielding layer, which is close to the glue film layer, is provided with convex conductor particles, and the first shielding layer and the second shielding layer are arranged to realize twice reflection of high-frequency interference signals, and simultaneously, redundant charges are led into a stratum, so that the shielding efficiency is greatly improved.
Description
Technical Field
The invention relates to the technical field of electronics, in particular to an electromagnetic shielding film, a circuit board and a preparation method of the electromagnetic shielding film.
Background
With the rapid development of the electronic industry, electronic products further develop toward miniaturization, light weight and high-density assembly, and the development of flexible circuit boards is greatly promoted, so that the integration of element devices and wire connection is realized. The flexible circuit board can be widely applied to industries such as mobile phones, liquid crystal displays, communication, aerospace and the like.
Under the push of the international market, the functional flexible circuit board is dominant in the flexible circuit board market, and an important index for evaluating the performance of the functional flexible circuit board is Electromagnetic shielding (EMI SHIELDING). With the integration of functions of communication devices such as mobile phones, internal components thereof are rapidly increased in frequency and speed. For example: in addition to the original audio transmission function, the camera function has become a necessary function, and the WLAN (Wireless Local Area Networks, wireless local area network), GPS (Global Positioning System ) and internet function have become popular, and the trend of rapid high-frequency and high-speed of the components is more unavoidable in addition to the integration of the future sensing components. Electromagnetic interference, signal attenuation during transmission, insertion loss and jitter problems inside and outside the component caused by high frequency and high speed driving are becoming serious.
At present, the electromagnetic shielding film commonly used by the existing circuit board comprises a shielding layer and a conductive adhesive layer, wherein the shielding layer is connected with the stratum of the circuit board through the conductive adhesive layer, so that interference charges are led into the stratum of the circuit board, and shielding is achieved. The electromagnetic shielding film with the structure has low shielding efficiency, so that the electromagnetic interference problem still exists in high-frequency and high-speed signal transmission.
Disclosure of Invention
The embodiment of the invention aims to provide an electromagnetic shielding film, a circuit board and a preparation method of the electromagnetic shielding film, which can effectively improve the shielding effectiveness of the electromagnetic shielding film.
In order to solve the technical problems, the embodiment of the invention provides an electromagnetic shielding film, which comprises a first shielding layer, an insulating layer, a second shielding layer and a glue film layer, wherein the first shielding layer, the insulating layer, the second shielding layer and the glue film layer are sequentially stacked, a hole is formed in the insulating layer, the first shielding layer and the second shielding layer are in contact with each other through the hole to realize electric conduction, one surface of the second shielding layer, which is close to the glue film layer, is a flat surface, and convex conductor particles are arranged on one surface of the second shielding layer, which is close to the glue film layer.
Preferably, the conductor particles include one or more of metal particles, carbon nanotube particles, and ferrite particles.
Preferably, the metal particles comprise single metal particles and/or alloy particles; wherein the single metal particles are made of any one material of aluminum, titanium, zinc, iron, nickel, chromium, cobalt, copper, silver and gold, and the alloy particles are made of any two or more materials of aluminum, titanium, zinc, iron, nickel, chromium, cobalt, copper, silver and gold.
Preferably, the conductor particles have the same shape and/or the conductor particles have the same pitch.
Preferably, the height of the conductor particles is 0.1 μm to 30 μm.
Preferably, the thickness of the first shielding layer is 0.1 μm-45 μm, the thickness of the second shielding layer is 0.1 μm-45 μm, the thickness of the insulating layer is 1 μm-80 μm, and the thickness of the adhesive film layer is 1 μm-80 μm.
Preferably, the adhesive film layer comprises an adhesive layer containing conductive particles; or, the adhesive film layer comprises an adhesive layer without conductive particles.
Preferably, the electromagnetic shielding film further comprises a protective film layer, and the protective film layer is arranged on one surface, far away from the adhesive film layer, of the first shielding layer.
In order to solve the same technical problems, the embodiment of the invention also provides a circuit board, which comprises a circuit board body and the electromagnetic shielding film, wherein the electromagnetic shielding film is pressed with the circuit board body through the adhesive film layer; and the conductor particles pierce through the adhesive film layer and are electrically connected with the stratum of the circuit board body.
The embodiment of the invention provides an electromagnetic shielding film and a circuit board, wherein the electromagnetic shielding film comprises a first shielding layer, an insulating layer, a second shielding layer and a film layer which are sequentially laminated, the insulating layer is provided with holes, the first shielding layer and the second shielding layer are in mutual contact through the holes to realize electric conduction, one surface of the second shielding layer, which is close to the film layer, is a flat surface, and the surface of the second shielding layer, which is close to the film layer, is provided with convex conductor particles, so that the conductor particles can pierce the film layer and are connected with a stratum of the circuit board when the electromagnetic shielding film is pressed with the circuit board, and the stratum connection of the electromagnetic shielding film and the circuit board is ensured; in addition, by arranging the first shielding layer and the second shielding layer, the high-frequency interference signals are reflected twice, and meanwhile, redundant charges are introduced into the stratum, so that the shielding efficiency is greatly improved; in addition, through setting up the insulating layer between first shielding layer and second shielding layer to increase the bendability of electromagnetic shielding film, the insulating layer has the hole simultaneously, makes the peel strength between first shielding layer and the second shielding layer great, and realizes the electric connection between first shielding layer and the second shielding layer through the hole of insulating layer.
In order to solve the same technical problems, the embodiment of the invention also provides a preparation method of the electromagnetic shielding film, which comprises the following steps:
forming a first shielding layer;
forming an insulating layer on the first shielding layer;
Forming a second shielding layer on the insulating layer; wherein, one surface of the second shielding layer far away from the insulating layer is a flat surface;
Forming convex conductor particles on the second shielding layer;
Forming a glue film layer on one surface of the second shielding layer, on which the conductor particles are formed;
the insulating layer is provided with a hole, and the first shielding layer and the second shielding layer are in contact with each other through the hole to realize electric conduction.
Preferably, the forming a first shielding layer specifically includes:
Forming a protective film layer on the carrier film;
Forming a first shielding layer on the protective film layer; or alternatively, the first and second heat exchangers may be,
Forming a first shielding layer on the surface of the peelable layer with the carrier;
Forming a protective film layer on the first shielding layer;
The peelable layer of the tape carrier is peeled off.
Preferably, a second shielding layer is formed on the insulating layer, specifically including:
A second shielding layer is formed on the insulating layer by one or more processes of physical roughening, electroless plating, physical vapor deposition, chemical vapor deposition, evaporative plating, sputter plating, electroplating, and hybrid plating.
Preferably, the forming of the convex conductor particles on the second shielding layer specifically includes:
Convex conductor particles are formed on the second shielding layer by one or more processes of physical roughening, chemical plating, physical vapor deposition, chemical vapor deposition, evaporation plating, sputter plating, electroplating, and hybrid plating.
As a preferable mode, a glue film layer is formed on one surface of the second shielding layer, on which the conductor particles are formed, specifically:
coating a glue film layer on the release film;
the adhesive film layer is pressed and transferred to one surface of the second shielding layer, on which the conductor particles are formed; or alternatively, the first and second heat exchangers may be,
And coating a glue film layer on one surface of the second shielding layer, on which the conductor particles are formed.
The embodiment of the invention provides a preparation method of an electromagnetic shielding film, which comprises the steps of firstly, forming a first shielding layer, then, forming an insulating layer on the first shielding layer, and then, forming a second shielding layer on the insulating layer; the surface of the second shielding layer, which is far away from the insulating layer, is a flat surface, convex conductor particles are formed on the second shielding layer, and finally a glue film layer is formed on the surface of the second shielding layer, on which the conductor particles are formed; the insulation layer is provided with a hole, the first shielding layer and the second shielding layer are in contact with each other through the hole to realize electric conduction, so that the prepared electromagnetic shielding film comprises a first shielding layer, an insulation layer, a second shielding layer and a glue film layer which are sequentially stacked, the insulation layer is provided with the hole, the first shielding layer and the second shielding layer are in contact with each other through the hole to realize electric conduction, one surface of the second shielding layer, which is close to the glue film layer, is a flat surface, and the surface of the second shielding layer, which is close to the glue film layer, is provided with convex conductor particles, so that the conductor particles can pierce the glue film layer and are connected with a stratum of the circuit board when the electromagnetic shielding film is pressed with the circuit board, and the stratum connection of the electromagnetic shielding film and the circuit board is ensured; in addition, by arranging the first shielding layer and the second shielding layer, the high-frequency interference signals are reflected twice, and meanwhile, redundant charges are introduced into the stratum, so that the shielding efficiency is greatly improved; in addition, through setting up the insulating layer between first shielding layer and second shielding layer to increase the bendability of electromagnetic shielding film, the insulating layer has the hole simultaneously, makes the peel strength between first shielding layer and the second shielding layer great, and realizes the electric connection between first shielding layer and the second shielding layer through the hole of insulating layer.
Drawings
Fig. 1 is a schematic structural view of an electromagnetic shielding film in an embodiment of the present invention;
Fig. 2 is a schematic structural view of another implementation of the electromagnetic shielding film in the embodiment of the present invention;
FIG. 3 is a cross-sectional view of an electromagnetic shielding film in an embodiment of the invention;
fig. 4 is a schematic structural view of a circuit board according to an embodiment of the present invention;
FIG. 5 is a schematic flow chart of a method for preparing an electromagnetic shielding film according to an embodiment of the invention;
1, a first shielding layer; 2. an insulating layer; 21. a void; 3. a second shielding layer; 31. conductor particles; 4. an adhesive film layer; 5. a protective film layer; 7. a circuit board body.
Detailed Description
The following description of the embodiments of the present invention will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present invention, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.
Referring to fig. 1, an electromagnetic shielding film according to a preferred embodiment of the present invention includes a first shielding layer 1, an insulating layer 2, a second shielding layer 3 and a glue film layer 4, where the first shielding layer 1, the insulating layer 2, the second shielding layer 3 and the glue film layer 4 are sequentially stacked, the insulating layer 2 has a hole 21, the first shielding layer 1 and the second shielding layer 3 are in contact with each other through the hole 21 to realize electrical conduction, a surface of the second shielding layer 3 close to the glue film layer 4 is a flat surface, and a surface of the second shielding layer 3 close to the glue film layer 4 is provided with convex conductor particles 31.
In the embodiment of the invention, the first shielding layer 1, the insulating layer 2, the second shielding layer 3 and the adhesive film layer 4 are sequentially laminated, and the first shielding layer 1 and the second shielding layer 3 are in mutual contact through the pores 21 to realize electric conduction by having the pores 21 on the insulating layer 2, one surface of the second shielding layer 3 close to the adhesive film layer 4 is a flat surface, and the surface of the second shielding layer 3 close to the adhesive film layer 4 is provided with the convex conductor particles 31, so that the conductor particles 31 can pierce the adhesive film layer 4 and be connected with the stratum of the circuit board when the electromagnetic shielding film is pressed with the circuit board, thereby ensuring the stratum connection of the electromagnetic shielding film and the circuit board; in addition, by arranging the first shielding layer 1 and the second shielding layer 3, the high-frequency interference signals are reflected twice, and meanwhile, redundant charges are introduced into the stratum, so that the shielding efficiency is greatly improved; further, by providing the insulating layer 2 between the first shielding layer 1 and the second shielding layer 3 to increase the bendability of the electromagnetic shielding film, the insulating layer 2 has the aperture 21, so that the peel strength between the first shielding layer 1 and the second shielding layer 3 is large, and the electrical connection between the first shielding layer 1 and the second shielding layer 3 is achieved through the aperture 21 of the insulating layer 2.
In the embodiment of the present invention, the area of the pores 21 is preferably 0.1 μm 2-1mm2, and the number of the pores 21 in the insulating layer 2 is preferably 10 to 1000 per square centimeter. By setting the area of the apertures 21 to preferably 0.1 μm 2-1mm2, the number of the apertures 21 per square centimeter in the insulating layer 2 is preferably set to 10 to 1000, so as to ensure that the insulating layer 2 has a sufficient number of the apertures 21 per unit area, thereby ensuring that the first shielding layer 1 and the second shielding layer 3 are in contact with each other to achieve electrical conduction.
In the embodiment of the present invention, the pores 21 may be regularly or irregularly distributed on the shielding layer 1; wherein, the pores 21 are regularly distributed on the shielding layer 1, which means that the pores 21 are uniformly distributed on the shielding layer 1 and have the same shape; the irregularly distributed pores 21 on the shielding layer 1 means that the respective pores 21 are irregularly shaped and randomly distributed on the shielding layer 1. Preferably, the shape of each aperture 21 is the same, and each aperture 21 is uniformly distributed on the shielding layer 1. Furthermore, the aperture 21 may be a circular aperture, or any other shape, and the present invention is illustrated only in the drawings in which the aperture 21 is a circular aperture, but any other shape of the aperture 21 is within the scope of the present invention.
As shown in fig. 1,2 and4, the conductor particles 31 may include a plurality of conductor particles 31, and the plurality of conductor particles 31 may be regularly or irregularly distributed on a surface of the second shielding layer 3 near the adhesive film layer 4; wherein, the regular distribution of the plurality of conductor particles 31 on the surface of the second shielding layer 3 near the adhesive film layer 4 means that the plurality of conductor particles 31 are uniformly distributed on the surface of the second shielding layer 3 near the adhesive film layer 4, wherein the shape of the plurality of conductor particles is the same; the irregular distribution of the plurality of conductor particles 31 on the surface of the second shielding layer 3 near the adhesive film layer 4 means that the plurality of conductor particles 31 are distributed on the surface of the second shielding layer 3 near the adhesive film layer 4 in different and disordered shapes. In the present embodiment, the shapes of the conductor particles 31 are the same, and/or the pitches of the conductor particles 31 are the same. Preferably, the shapes of the plurality of conductor particles 31 are the same, and the plurality of conductor particles 31 are uniformly distributed on one surface of the second shielding layer 3 close to the adhesive film layer 4. In addition, the surface of the second shielding layer 3 away from the adhesive film layer 4 may be any shape, for example, a flat surface, a non-flat surface with a wavy shape, or other rough surface. The drawings only illustrate the second shielding layer 3 having a flat surface on a side away from the adhesive film layer 4, but any other shape is within the scope of the present invention.
In an implementation, the second shielding layer 3 may be formed first, and then the conductor particles 31 may be formed on the second shielding layer 3 through other processes. Of course, the second shielding layer 3 and the conductor particles 31 may also be a unitary structure formed by a one-shot molding process.
Preferably, the height of the conductor particles 31 is 0.1 μm to 30 μm; the conductor particles 31 may be spaced from the outer surface of the adhesive film layer 4, or may contact the outer surface of the adhesive film layer 4 or extend out of the outer surface of the adhesive film layer 4. In addition, the outer surface of the adhesive film layer 4 may be a flat surface without undulation, or may be an uneven surface with gentle undulation.
It should be noted that the shapes of the conductor particles 31 in fig. 1,2 and 4 are merely exemplary, and the conductor particles 31 may be in other shapes such as clusters, ice-hanging shapes, stalactites, dendrites, etc. due to differences in process means and parameters. In addition, the conductor particles 31 in the embodiment of the present invention are not limited to the shape shown in the drawings and described above, and any conductor particles 31 having piercing and conducting functions are within the scope of the present invention.
Preferably, the thickness of the first shielding layer 1 is 0.1 μm-45 μm, the thickness of the second shielding layer 3 is 0.1 μm-45 μm, the thickness of the insulating layer 2 is 1 μm-80 μm, and the thickness of the adhesive film layer 4 is 1 μm-80 μm. The adhesive film layer 4 is made of the following materials: modified epoxy resins, acrylic, modified rubbers, and modified thermoplastic polyimides. It will be appreciated that, in order to ensure good electrical conductivity of the first shielding layer 1 and the second shielding layer 3, the first shielding layer 1 and the second shielding layer 3 respectively include one or more of a metal shielding layer, a carbon nanotube shielding layer, a ferrite shielding layer and a graphene shielding layer. Wherein the metal shielding layer comprises a single metal shielding layer and/or an alloy shielding layer; wherein the single metal shielding layer is made of any one material of aluminum, titanium, zinc, iron, nickel, chromium, cobalt, copper, silver and gold, and the alloy shielding layer is made of any two or more materials of aluminum, titanium, zinc, iron, nickel, chromium, cobalt, copper, silver and gold.
In the embodiment of the present invention, the conductor particles 31 include one or more of metal particles, carbon nanotube particles, and ferrite particles. Further, the metal particles include single metal particles and/or alloy particles; wherein the single metal particles are made of any one material of aluminum, titanium, zinc, iron, nickel, chromium, cobalt, copper, silver and gold, and the alloy particles are made of any two or more materials of aluminum, titanium, zinc, iron, nickel, chromium, cobalt, copper, silver and gold. The conductor particles 31 may be the same as or different from the material of the first shielding layer 1 or the second shielding layer 3.
In the embodiment of the present invention, in order to further ensure the formation connection between the electromagnetic shielding film and the circuit board, the adhesive film layer 4 in the embodiment includes an adhesive layer containing conductive particles. The adhesive layer 4 comprises an adhesive layer containing conductive particles so as to improve the conductive capability of the adhesive layer 4, thereby further ensuring the stratum connection of the electromagnetic shielding film and the circuit board. Of course, the adhesive film layer 4 may include an adhesive layer without conductive particles to reduce insertion loss of the circuit board with the electromagnetic shielding film, thereby improving flexibility of the circuit board while improving shielding efficiency.
The conductive particles may be conductive particles separated from each other or large-particle conductive particles agglomerated; when the conductive particles are mutually separated conductive particles, the ground conductivity of the adhesive film layer 4 can be further improved; and when the conductive particles are large-particle conductive particles formed by agglomeration, the piercing strength can be increased.
As shown in fig. 2 and fig. 4, the electromagnetic shielding film of the present embodiment further includes a protective film layer 5, where the protective film layer 5 is disposed on a surface of the first shielding layer 1 away from the adhesive film layer 4. Since the protective film layer 5 has an insulating effect, shielding effectiveness of the first shielding layer 1 and the second shielding layer 3 is ensured; in addition, the protective film layer 5 has a protective function to ensure that the first shielding layer 1 is not scratched and damaged in the use process, and maintains the high shielding effectiveness of the first shielding layer 1. The protective film layer 5 comprises a PPS film layer, a PEN film layer, a polyester film layer, a polyimide film layer, a film layer formed by curing epoxy resin ink, a film layer formed by curing polyurethane ink, a film layer formed by curing modified acrylic resin or a film layer formed by curing polyimide resin. The surface of the protective film layer 5, which is far away from the first shielding layer 1, may be further provided with a carrier film, which supports the protective film layer 5, so that subsequent processing is facilitated.
It should be noted that, the first shielding layer 1, the insulating layer 2, and the second shielding layer 3 in this embodiment may have a single-layer structure or a multi-layer structure, respectively. In order to enhance the electromagnetic shielding effect, the first shielding layer 1, the insulating layer 2, and the second shielding layer 3 of the embodiment of the present invention may be provided in plurality. Preferably, when the first shielding layer 1, the insulating layer 2 and the second shielding layer 3 are respectively plural, the first shielding layer 1, the insulating layer 2 and the second shielding layer 3 are sequentially arranged at intervals, for example, when the first shielding layer 1, the insulating layer 2 and the second shielding layer 3 are respectively 2, the arrangement sequence may be as follows: one of the first shielding layers 1, one of the insulating layers 2, one of the second shielding layers 3, the other of the first shielding layers 1, the other of the insulating layers 2, the other of the second shielding layers 3, and the like, are not described in detail herein. When the second shielding layers 3 are multiple layers, each of the second shielding layers 3 may have a convex conductor particle 31 on a surface thereof adjacent to the adhesive film layer 4. In addition, the first shielding layer 1 and the second shielding layer 3 of the present embodiment may be provided in a mesh shape, a foam shape, or the like, according to the actual production and application requirements.
In order to solve the same technical problems, the embodiment of the invention also provides a circuit board, which comprises a circuit board body 7 and the electromagnetic shielding film, wherein the electromagnetic shielding film is pressed with the circuit board body 7 through the adhesive film layer 4; the conductor particles 31 pierce the adhesive film layer 4 and are electrically connected with the ground layer of the circuit board body 7.
Referring to fig. 4, in order to solve the same technical problems, the embodiment of the invention further provides a circuit board, which comprises a circuit board body 7 and the electromagnetic shielding film, wherein the electromagnetic shielding film is pressed with the circuit board body 7 through the adhesive film layer 4; the conductor particles 31 pierce the adhesive film layer 4 and are electrically connected with the ground layer of the circuit board body 7.
In the embodiment of the present invention, the conductor particles 31 can pierce the adhesive film layer 4 and connect with the stratum of the circuit board body 7 when the electromagnetic shielding film is pressed against the circuit board body 7, so as to ensure that the first shielding layer 1 and the second shielding layer 3 connect with the stratum of the circuit board body 7, thereby realizing that the interference charges in the first shielding layer 1 and the second shielding layer 3 are led into the ground, and avoiding that the normal operation of the circuit board is affected by the interference sources formed by the accumulation of the interference charges.
Preferably, the circuit board body 7 is one of flexible single-sided, flexible double-sided, flexible multi-layer board and rigid-flex board.
Referring to fig. 5, in order to solve the same technical problem, an embodiment of the present invention further provides a method for preparing an electromagnetic shielding film, including the following steps:
S11, forming a first shielding layer 1;
s12, forming an insulating layer 2 on the first shielding layer 1;
S13, forming a second shielding layer 3 on the insulating layer 2; wherein, the surface of the second shielding layer 3 away from the insulating layer 2 is a flat surface;
S14, forming convex conductor particles 31 on the second shielding layer 3;
S15, forming a glue film layer 4 on the surface of the second shielding layer 3 where the conductor particles 31 are formed;
Wherein, the insulating layer 2 is provided with a hole 21, and the first shielding layer 1 and the second shielding layer 3 are contacted with each other through the hole 21 to realize electric conduction.
In step S11, the forming the first shielding layer 1 specifically includes:
Forming a protective film layer 5 on the carrier film;
Forming a first shielding layer 1 on the protective film layer 5; wherein the first shielding layer 1 may be formed on the protective film layer 5 by one or more processes of physical roughening, chemical plating, physical vapor deposition, chemical vapor deposition, evaporation plating, sputtering plating, electroplating, and mixed plating; or alternatively, the first and second heat exchangers may be,
Forming a first shielding layer 1 on the surface of the peelable layer with a carrier;
forming a protective film layer 5 on the first shielding layer 1;
peeling the peelable layer of the tape carrier;
Wherein the first shielding layer 1 may be formed on the peelable layer surface of the tape carrier by one or more processes of physical roughening, electroless plating, physical vapor deposition, chemical vapor deposition, evaporation plating, sputter plating, electroplating, and hybrid plating.
In the embodiment of the present invention, the insulating layer 2 may be made to have the aperture 21 enabling the first shielding layer 1 and the second shielding layer 2 to be electrically conducted by:
Firstly, performing laser processing or die cutting processing on a PPS, PEN or polyimide film and the like to form an insulating layer 2 with a hole 21, wherein the thickness is preferably 1-80 mu m, then forming a first shielding layer 1 and/or a second shielding layer 3 on the surface of the insulating layer 2 with the hole 21 by sputtering and the like, so that when the first shielding layer 1 and/or the second shielding layer 3 are formed, part of materials for preparing the first shielding layer 1 and/or the second shielding layer 3 extend into the hole 21 to realize metal filling of the hole 21, and the first shielding layer 1 and the second shielding layer 3 can be in contact with each other through the hole 21 to realize electric conduction; or the pores 21 are directly treated by electroless plating or the like, so that a metal layer is formed on the inner surfaces of the pores 21, thereby enabling the first shielding layer 1 and the second shielding layer 3 to be in contact with each other through the pores 21 to realize electric conduction. Further, since the insulating layer 2 is made of an elastic material such as PPS, PEN, or polyimide film, the flexibility of the electromagnetic shielding film can be improved by providing the insulating layer 2 with elasticity.
In step S13, the second shielding layer 3 may be formed on the insulating layer 2 through one or more processes of physical roughening, electroless plating, physical vapor deposition, chemical vapor deposition, evaporation plating, sputter plating, electroplating, and hybrid plating.
In step S14, forming convex conductor particles 31 on the second shielding layer 3 specifically includes:
Convex conductor particles 31 are formed on the second shielding layer 3 by one or more processes of physical roughening, electroless plating, physical vapor deposition, chemical vapor deposition, evaporation plating, sputter plating, electroplating, and hybrid plating.
In step S15, a glue film layer 4 is formed on the surface of the second shielding layer 3 on which the conductor particles 31 are formed, specifically:
coating a glue film layer 4 on the release film;
pressing and transferring the adhesive film layer 4 to one surface of the second shielding layer 3, on which the conductor particles 31 are formed; or alternatively, the first and second heat exchangers may be,
A film layer 4 is coated on the surface of the second shielding layer 3 on which the conductor particles 31 are formed.
In summary, the embodiment of the invention provides an electromagnetic shielding film, a circuit board and a preparation method of the electromagnetic shielding film, wherein the electromagnetic shielding film comprises a first shielding layer 1, an insulating layer 2, a second shielding layer 3 and a glue film layer 4 which are sequentially stacked, the insulating layer 2 is provided with a hole 21, the first shielding layer 1 and the second shielding layer 3 are in mutual contact through the hole 21 to realize electric conduction, one surface of the second shielding layer 3, which is close to the glue film layer 4, is a flat surface, and one surface of the second shielding layer 3, which is close to the glue film layer 4, is provided with convex conductor particles 31, so that the conductor particles 31 can pierce the glue film layer 4 and are connected with a stratum of the circuit board when the electromagnetic shielding film is pressed with the circuit board, and the stratum connection of the electromagnetic shielding film and the circuit board is ensured; in addition, by arranging the first shielding layer 1 and the second shielding layer 3, the high-frequency interference signals are reflected twice, and meanwhile, redundant charges are introduced into the stratum, so that the shielding efficiency is greatly improved; further, by providing the insulating layer 2 between the first shielding layer 1 and the second shielding layer 3 to increase the bendability of the electromagnetic shielding film, the insulating layer 2 has the aperture 21, so that the peel strength between the first shielding layer 1 and the second shielding layer 3 is large, and the electrical connection between the first shielding layer 1 and the second shielding layer 3 is achieved through the aperture 21 of the insulating layer 2.
The foregoing is merely a preferred embodiment of the present invention, and it should be noted that modifications and substitutions can be made by those skilled in the art without departing from the technical principles of the present invention, and these modifications and substitutions should also be considered as being within the scope of the present invention.
Claims (14)
1. The electromagnetic shielding film is characterized by comprising a first shielding layer, an insulating layer, a second shielding layer and a film layer, wherein the first shielding layer, the insulating layer, the second shielding layer and the film layer are sequentially laminated, the insulating layer is provided with holes, the first shielding layer and the second shielding layer are in mutual contact through the holes to realize electric conduction, one surface of the second shielding layer, which is close to the film layer, is a flat surface, and one surface of the second shielding layer, which is close to the film layer, is provided with convex conductor particles; the area of the pores is 0.1 mu m 2-1mm2, and the number of the pores in the insulating layer is 10-1000 per square centimeter.
2. The electromagnetic shielding film of claim 1, wherein the conductor particles comprise one or more of metal particles, carbon nanotube particles, and ferrite particles.
3. The electromagnetic shielding film of claim 2, wherein the metal particles comprise single metal particles and/or alloy particles; wherein the single metal particles are made of any one material of aluminum, titanium, zinc, iron, nickel, chromium, cobalt, copper, silver and gold, and the alloy particles are made of any two or more materials of aluminum, titanium, zinc, iron, nickel, chromium, cobalt, copper, silver and gold.
4. The electromagnetic shielding film according to claim 1, wherein the conductor particles are identical in shape and/or the conductor particles are identical in pitch.
5. The electromagnetic shielding film according to claim 1, wherein the conductor particles have a height of 0.1 μm to 30 μm.
6. The electromagnetic shielding film according to any one of claims 1 to 5, wherein the first shielding layer has a thickness of 0.1 μm to 45 μm, the second shielding layer has a thickness of 0.1 μm to 45 μm, the insulating layer has a thickness of 1 μm to 80 μm, and the adhesive film layer has a thickness of 1 μm to 80 μm.
7. The electromagnetic shielding film according to any one of claims 1 to 5, wherein the adhesive film layer includes an adhesive layer containing conductive particles; or, the adhesive film layer comprises an adhesive layer without conductive particles.
8. The electromagnetic shielding film of any one of claims 1-5, further comprising a protective film layer disposed on a side of the first shielding layer remote from the adhesive film layer.
9. A circuit board, characterized by comprising a circuit board body and the electromagnetic shielding film according to any one of claims 1-8, wherein the electromagnetic shielding film is pressed with the circuit board body through the adhesive film layer; and the conductor particles pierce through the adhesive film layer and are electrically connected with the stratum of the circuit board body.
10. The preparation method of the electromagnetic shielding film is characterized by comprising the following steps of:
forming a first shielding layer;
forming an insulating layer on the first shielding layer;
Forming a second shielding layer on the insulating layer; wherein, one surface of the second shielding layer far away from the insulating layer is a flat surface;
Forming convex conductor particles on one surface of the second shielding layer away from the insulating layer;
Forming a glue film layer on one surface of the second shielding layer, on which the conductor particles are formed;
Wherein, the insulating layer is provided with a hole, and the first shielding layer and the second shielding layer are contacted with each other through the hole to realize electric conduction; the area of the pores is 0.1 mu m 2-1mm2, and the number of the pores in the insulating layer is 10-1000 per square centimeter.
11. The method for preparing an electromagnetic shielding film according to claim 10, wherein the forming the first shielding layer specifically comprises:
Forming a protective film layer on the carrier film;
Forming a first shielding layer on the protective film layer; or alternatively, the first and second heat exchangers may be,
Forming a first shielding layer on the surface of the peelable layer with the carrier;
Forming a protective film layer on the first shielding layer;
The peelable layer of the tape carrier is peeled off.
12. The method for producing an electromagnetic shielding film according to claim 10, wherein forming a second shielding layer on the insulating layer, specifically comprises:
A second shielding layer is formed on the insulating layer by one or more processes of physical roughening, electroless plating, physical vapor deposition, chemical vapor deposition, evaporative plating, sputter plating, electroplating, and hybrid plating.
13. The method for producing an electromagnetic shielding film according to any one of claims 10 to 12, wherein forming convex conductor particles on the second shielding layer specifically comprises:
Convex conductor particles are formed on the second shielding layer by one or more processes of physical roughening, chemical plating, physical vapor deposition, chemical vapor deposition, evaporation plating, sputter plating, electroplating, and hybrid plating.
14. The method for producing an electromagnetic shielding film according to any one of claims 10 to 12, wherein a film layer is formed on a surface of the second shielding layer on which the conductor particles are formed, specifically:
coating a glue film layer on the release film;
the adhesive film layer is pressed and transferred to one surface of the second shielding layer, on which the conductor particles are formed; or alternatively, the first and second heat exchangers may be,
And coating a glue film layer on one surface of the second shielding layer, on which the conductor particles are formed.
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Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102510712A (en) * | 2011-11-14 | 2012-06-20 | 广州方邦电子有限公司 | Paper-thin screened film with extremely high screening efficiency and manufacturing method therefor |
| CN108323143A (en) * | 2018-03-14 | 2018-07-24 | 广州方邦电子股份有限公司 | The preparation method of electromagnetic shielding film, wiring board and electromagnetic shielding film |
| CN108323144A (en) * | 2018-03-14 | 2018-07-24 | 广州方邦电子股份有限公司 | The preparation method of electromagnetic shielding film, wiring board and electromagnetic shielding film |
| CN208754634U (en) * | 2018-07-27 | 2019-04-16 | 广州方邦电子股份有限公司 | Electromagnetic shielding film and wiring board |
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| KR100780283B1 (en) * | 2004-09-01 | 2007-11-28 | 삼성코닝 주식회사 | Electromagnetic shielding film and fabrication method thereof |
| JP6240376B2 (en) * | 2012-07-13 | 2017-11-29 | タツタ電線株式会社 | Shield film and shield printed wiring board |
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Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102510712A (en) * | 2011-11-14 | 2012-06-20 | 广州方邦电子有限公司 | Paper-thin screened film with extremely high screening efficiency and manufacturing method therefor |
| CN108323143A (en) * | 2018-03-14 | 2018-07-24 | 广州方邦电子股份有限公司 | The preparation method of electromagnetic shielding film, wiring board and electromagnetic shielding film |
| CN108323144A (en) * | 2018-03-14 | 2018-07-24 | 广州方邦电子股份有限公司 | The preparation method of electromagnetic shielding film, wiring board and electromagnetic shielding film |
| CN208754634U (en) * | 2018-07-27 | 2019-04-16 | 广州方邦电子股份有限公司 | Electromagnetic shielding film and wiring board |
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