CN110783017A - Conductive adhesive film, circuit board and preparation method of conductive adhesive film - Google Patents
Conductive adhesive film, circuit board and preparation method of conductive adhesive film Download PDFInfo
- Publication number
- CN110783017A CN110783017A CN201811423719.0A CN201811423719A CN110783017A CN 110783017 A CN110783017 A CN 110783017A CN 201811423719 A CN201811423719 A CN 201811423719A CN 110783017 A CN110783017 A CN 110783017A
- Authority
- CN
- China
- Prior art keywords
- layer
- conductive
- adhesive film
- conducting
- resin
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- 239000002313 adhesive film Substances 0.000 title claims abstract description 189
- 238000002360 preparation method Methods 0.000 title abstract description 6
- 239000010410 layer Substances 0.000 claims abstract description 393
- 239000011347 resin Substances 0.000 claims abstract description 110
- 229920005989 resin Polymers 0.000 claims abstract description 110
- 239000002245 particle Substances 0.000 claims abstract description 93
- 239000004020 conductor Substances 0.000 claims abstract description 81
- 239000012790 adhesive layer Substances 0.000 claims abstract description 60
- 230000000149 penetrating effect Effects 0.000 claims abstract description 7
- 229910000831 Steel Inorganic materials 0.000 claims description 49
- 239000010959 steel Substances 0.000 claims description 49
- 239000003292 glue Substances 0.000 claims description 25
- 238000000034 method Methods 0.000 claims description 20
- 230000001681 protective effect Effects 0.000 claims description 18
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims description 16
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 claims description 16
- 229910052751 metal Inorganic materials 0.000 claims description 13
- 239000002184 metal Substances 0.000 claims description 13
- 238000007747 plating Methods 0.000 claims description 12
- 230000001070 adhesive effect Effects 0.000 claims description 11
- 239000000853 adhesive Substances 0.000 claims description 10
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims description 9
- 239000011248 coating agent Substances 0.000 claims description 9
- 238000000576 coating method Methods 0.000 claims description 9
- VYZAMTAEIAYCRO-UHFFFAOYSA-N Chromium Chemical compound [Cr] VYZAMTAEIAYCRO-UHFFFAOYSA-N 0.000 claims description 8
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 claims description 8
- BQCADISMDOOEFD-UHFFFAOYSA-N Silver Chemical compound [Ag] BQCADISMDOOEFD-UHFFFAOYSA-N 0.000 claims description 8
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 claims description 8
- HCHKCACWOHOZIP-UHFFFAOYSA-N Zinc Chemical compound [Zn] HCHKCACWOHOZIP-UHFFFAOYSA-N 0.000 claims description 8
- 239000000956 alloy Substances 0.000 claims description 8
- 229910045601 alloy Inorganic materials 0.000 claims description 8
- 229910052782 aluminium Inorganic materials 0.000 claims description 8
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 claims description 8
- 229910052804 chromium Inorganic materials 0.000 claims description 8
- 239000011651 chromium Substances 0.000 claims description 8
- 229910017052 cobalt Inorganic materials 0.000 claims description 8
- 239000010941 cobalt Substances 0.000 claims description 8
- GUTLYIVDDKVIGB-UHFFFAOYSA-N cobalt atom Chemical compound [Co] GUTLYIVDDKVIGB-UHFFFAOYSA-N 0.000 claims description 8
- 229910052802 copper Inorganic materials 0.000 claims description 8
- 239000010949 copper Substances 0.000 claims description 8
- PCHJSUWPFVWCPO-UHFFFAOYSA-N gold Chemical compound [Au] PCHJSUWPFVWCPO-UHFFFAOYSA-N 0.000 claims description 8
- 229910052737 gold Inorganic materials 0.000 claims description 8
- 239000010931 gold Substances 0.000 claims description 8
- 229910052742 iron Inorganic materials 0.000 claims description 8
- 229910052759 nickel Inorganic materials 0.000 claims description 8
- 229910052709 silver Inorganic materials 0.000 claims description 8
- 239000004332 silver Substances 0.000 claims description 8
- 239000010936 titanium Substances 0.000 claims description 8
- 229910052719 titanium Inorganic materials 0.000 claims description 8
- 229910052725 zinc Inorganic materials 0.000 claims description 8
- 239000011701 zinc Substances 0.000 claims description 8
- 238000003825 pressing Methods 0.000 claims description 7
- 238000002844 melting Methods 0.000 claims description 6
- 230000008018 melting Effects 0.000 claims description 6
- 239000002041 carbon nanotube Substances 0.000 claims description 5
- 229910021393 carbon nanotube Inorganic materials 0.000 claims description 5
- 238000001816 cooling Methods 0.000 claims description 5
- 229910000859 α-Fe Inorganic materials 0.000 claims description 5
- 229910021389 graphene Inorganic materials 0.000 claims description 4
- 238000005229 chemical vapour deposition Methods 0.000 claims description 3
- 238000009713 electroplating Methods 0.000 claims description 3
- 230000008020 evaporation Effects 0.000 claims description 3
- 238000001704 evaporation Methods 0.000 claims description 3
- 238000005240 physical vapour deposition Methods 0.000 claims description 3
- 238000007788 roughening Methods 0.000 claims description 3
- 238000004544 sputter deposition Methods 0.000 claims description 3
- 239000000126 substance Substances 0.000 claims description 3
- 238000007711 solidification Methods 0.000 claims description 2
- 230000008023 solidification Effects 0.000 claims description 2
- 238000004519 manufacturing process Methods 0.000 description 11
- 239000000084 colloidal system Substances 0.000 description 5
- 239000000463 material Substances 0.000 description 5
- 238000010586 diagram Methods 0.000 description 4
- 239000002923 metal particle Substances 0.000 description 4
- 238000005452 bending Methods 0.000 description 3
- 239000004925 Acrylic resin Substances 0.000 description 2
- 229920000178 Acrylic resin Polymers 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 238000009434 installation Methods 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 229920001721 polyimide Polymers 0.000 description 2
- 230000003014 reinforcing effect Effects 0.000 description 2
- 238000006467 substitution reaction Methods 0.000 description 2
- 229920006269 PPS film Polymers 0.000 description 1
- NIXOWILDQLNWCW-UHFFFAOYSA-N acrylic acid group Chemical group C(C=C)(=O)O NIXOWILDQLNWCW-UHFFFAOYSA-N 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 238000011109 contamination Methods 0.000 description 1
- 210000001787 dendrite Anatomy 0.000 description 1
- 239000000428 dust Substances 0.000 description 1
- 229920001971 elastomer Polymers 0.000 description 1
- 239000003822 epoxy resin Substances 0.000 description 1
- 238000005187 foaming Methods 0.000 description 1
- LNEPOXFFQSENCJ-UHFFFAOYSA-N haloperidol Chemical class C1CC(O)(C=2C=CC(Cl)=CC=2)CCN1CCCC(=O)C1=CC=C(F)C=C1 LNEPOXFFQSENCJ-UHFFFAOYSA-N 0.000 description 1
- 239000012535 impurity Substances 0.000 description 1
- 238000003780 insertion Methods 0.000 description 1
- 230000037431 insertion Effects 0.000 description 1
- 230000001788 irregular Effects 0.000 description 1
- 238000004377 microelectronic Methods 0.000 description 1
- 238000002156 mixing Methods 0.000 description 1
- 238000000465 moulding Methods 0.000 description 1
- 238000004806 packaging method and process Methods 0.000 description 1
- 229920000647 polyepoxide Polymers 0.000 description 1
- 229920006267 polyester film Polymers 0.000 description 1
- 239000009719 polyimide resin Substances 0.000 description 1
- 239000004814 polyurethane Substances 0.000 description 1
- 229920002635 polyurethane Polymers 0.000 description 1
- 239000005060 rubber Substances 0.000 description 1
- 239000002356 single layer Substances 0.000 description 1
- 229920006259 thermoplastic polyimide Polymers 0.000 description 1
- 229920005992 thermoplastic resin Polymers 0.000 description 1
- 229920001187 thermosetting polymer Polymers 0.000 description 1
Images
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01B—CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES
- H01B5/00—Non-insulated conductors or conductive bodies characterised by their form
- H01B5/14—Non-insulated conductors or conductive bodies characterised by their form comprising conductive layers or films on insulating-supports
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01B—CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES
- H01B13/00—Apparatus or processes specially adapted for manufacturing conductors or cables
- H01B13/0026—Apparatus for manufacturing conducting or semi-conducting layers, e.g. deposition of metal
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01R—ELECTRICALLY-CONDUCTIVE CONNECTIONS; STRUCTURAL ASSOCIATIONS OF A PLURALITY OF MUTUALLY-INSULATED ELECTRICAL CONNECTING ELEMENTS; COUPLING DEVICES; CURRENT COLLECTORS
- H01R12/00—Structural associations of a plurality of mutually-insulated electrical connecting elements, specially adapted for printed circuits, e.g. printed circuit boards [PCB], flat or ribbon cables, or like generally planar structures, e.g. terminal strips, terminal blocks; Coupling devices specially adapted for printed circuits, flat or ribbon cables, or like generally planar structures; Terminals specially adapted for contact with, or insertion into, printed circuits, flat or ribbon cables, or like generally planar structures
- H01R12/50—Fixed connections
- H01R12/51—Fixed connections for rigid printed circuits or like structures
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01R—ELECTRICALLY-CONDUCTIVE CONNECTIONS; STRUCTURAL ASSOCIATIONS OF A PLURALITY OF MUTUALLY-INSULATED ELECTRICAL CONNECTING ELEMENTS; COUPLING DEVICES; CURRENT COLLECTORS
- H01R13/00—Details of coupling devices of the kinds covered by groups H01R12/70 or H01R24/00 - H01R33/00
- H01R13/648—Protective earth or shield arrangements on coupling devices, e.g. anti-static shielding
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01R—ELECTRICALLY-CONDUCTIVE CONNECTIONS; STRUCTURAL ASSOCIATIONS OF A PLURALITY OF MUTUALLY-INSULATED ELECTRICAL CONNECTING ELEMENTS; COUPLING DEVICES; CURRENT COLLECTORS
- H01R4/00—Electrically-conductive connections between two or more conductive members in direct contact, i.e. touching one another; Means for effecting or maintaining such contact; Electrically-conductive connections having two or more spaced connecting locations for conductors and using contact members penetrating insulation
- H01R4/04—Electrically-conductive connections between two or more conductive members in direct contact, i.e. touching one another; Means for effecting or maintaining such contact; Electrically-conductive connections having two or more spaced connecting locations for conductors and using contact members penetrating insulation using electrically conductive adhesives
-
- 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
- H05K1/00—Printed circuits
- H05K1/02—Details
- H05K1/0213—Electrical arrangements not otherwise provided for
- H05K1/0216—Reduction of cross-talk, noise or electromagnetic interference
- H05K1/0218—Reduction of cross-talk, noise or electromagnetic interference by printed shielding conductors, ground planes or power plane
-
- 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
- H05K2201/00—Indexing scheme relating to printed circuits covered by H05K1/00
- H05K2201/07—Electric details
- H05K2201/0707—Shielding
- H05K2201/0715—Shielding provided by an outer layer of PCB
Abstract
The embodiment of the invention provides a conductive adhesive film, a circuit board and a preparation method of the conductive adhesive film, wherein the conductive adhesive film comprises a first conductive layer, a second conductive layer, a conductive adhesive layer and an adhesive film layer; a resin bulge is arranged at the first through hole of the first conducting layer; the second conducting layer is arranged on one side, close to the resin bulge, of the first conducting layer, and a bulge part is formed at the position, covered by the second conducting layer, of the resin bulge; the resin protrusion is formed by the resin flowing from one side of the first through hole to the other side and then solidifying. When the conductors are laminated through the conductive adhesive film, the conductive adhesive film is electrically connected with one conductor through the conductive adhesive layer and is electrically connected with the other conductor through the protruding part penetrating the adhesive film layer, and reliable connection between the conductors is achieved. The first conducting layer and the second conducting layer arranged in the conducting adhesive film increase the overlapping rate of conducting particles in the conducting adhesive film, reduce the resistance of the conducting adhesive film and improve the conducting performance of the conducting adhesive film, so that the electrical connection between conductors is ensured.
Description
Technical Field
The invention relates to the technical field of electronics, in particular to a conductive adhesive film, a circuit board and a preparation method of the conductive adhesive film.
Background
The conductive adhesive film is a lead-free connecting material, which provides mechanical and electrical connection between the components and the circuit board, and thus is gradually and widely used in various electronic fields such as microelectronic packaging, printed circuit boards, conductive circuit bonding, and the like.
At present, the existing conductive adhesive film is generally prepared by mixing a large amount of conductive particles in the adhesive, so that the conductive adhesive film can provide mechanical connection and electrical connection simultaneously; in practical application, the conductive adhesive film is adhered between the conductors, and one surface of the conductive adhesive film is adhered to one of the conductors, and the other surface of the conductive adhesive film is adhered to the other conductor, so that the conduction between the conductors is realized. However, in the process of implementing the invention, the inventor finds that the prior art has at least the following problems: under the influence of the manufacturing process, the overlapping rate of conductive particles in the traditional conductive adhesive film is generally low, so that the resistance of the conductive adhesive film is high; particularly, under the condition of high temperature, after the conductive adhesive film is heated, the colloid expands, so that the conductive particles are pulled apart, the overlapping rate of the conductive particles is further reduced, and the resistance of the conductive adhesive film is rapidly increased.
Disclosure of Invention
The invention aims to provide a conductive adhesive film, a circuit board and a preparation method of the conductive adhesive film, which are used for solving the technical problem that the existing conductive adhesive film is high in resistance so as to reduce the resistance of the conductive adhesive film.
In order to solve the above technical problems, the present invention provides a conductive adhesive film, which includes a first conductive layer, a second conductive layer, a conductive adhesive layer and an adhesive layer;
the first conducting layer is provided with a first through hole penetrating through the upper surface and the lower surface of the first conducting layer, and a resin bulge is arranged at the first through hole; the second conducting layer is arranged on one side, close to the resin bulge, of the first conducting layer, and a bulge part is formed at the position, covered by the second conducting layer, of the resin bulge; the adhesive film layer is arranged on one surface, far away from the first conducting layer, of the second conducting layer, and the conductive adhesive layer is arranged on one surface, far away from the second conducting layer, of the first conducting layer; wherein the resin protrusion is formed by solidification of resin after flowing from one side to the other side of the first through hole.
Preferably, the resin protrusion is formed by solidifying at a curing temperature after resin flows from one side to the other side of the first through hole at normal temperature; or the like, or, alternatively,
the resin protrusion is formed by cooling and solidifying after resin flows from one side to the other side of the first through hole at a melting temperature.
Preferably, the surface of the convex part is provided with conductor particles; the height of the conductor particles is 1-30 μm.
Preferably, the shape of the conductive particles is cluster-like, ice-hanging-like, stalactite-like, or dendritic.
Preferably, the conductor particles are plural; a plurality of conductor particles are regularly or irregularly distributed on the surface of the convex part; the plurality of conductor particles are continuously or discontinuously distributed on the surface of the convex part.
Preferably, the adhesive layer comprises an adhesive layer containing conductive particles; or the adhesive film layer comprises an adhesion layer without conductive particles.
Preferably, the first conductive layer and the second conductive layer respectively include one or more of a metal conductive layer, a carbon nanotube conductive layer, a ferrite conductive layer, and a graphene conductive layer.
Preferably, the metal conductive layer comprises a single metal conductive layer and/or an alloy conductive layer; the single metal conducting layer is made of any one of aluminum, titanium, zinc, iron, nickel, chromium, cobalt, copper, silver and gold, and the alloy conducting layer is made of any two or more of aluminum, titanium, zinc, iron, nickel, chromium, cobalt, copper, silver and gold.
Preferably, the number of the first through holes in the first conductive layer is 10-1000 per square centimeter; and/or the cross-sectional area of the first through hole is 0.1 mu m
2-1mm
2。
As a preferred scheme, the conductive adhesive film further comprises a first protective film layer and a second protective film layer, wherein the first protective film layer is arranged on one surface of the adhesive film layer, which is far away from the second conductive layer; the second protective film layer is arranged on one surface, far away from the first conductive layer, of the conductive adhesive layer.
Compared with the prior art, the embodiment of the invention discloses a conductive adhesive film, wherein the conductive adhesive layer, the first conductive layer and the adhesive film layer are sequentially arranged, the resin bulge is arranged at the first through hole of the first conductive layer, and the second conductive layer is provided with the bulge part at the position covering the resin bulge, so that when the conductors are laminated through the conductive adhesive film, the conductive adhesive film can be electrically connected with one conductor through the conductive adhesive layer, and simultaneously the adhesive film layer is pierced through the bulge part to be electrically connected with the other conductor, thereby realizing the reliable connection between the conductors; meanwhile, the first conducting layer and the second conducting layer are arranged in the conducting adhesive film, so that the overlapping rate of conducting particles in the conducting adhesive film is increased, and the problem that the resistance of the conducting adhesive film is increased due to the fact that the conducting particles are pulled apart due to expansion of the adhesive body at high temperature can be solved, the resistance of the conducting adhesive film is greatly reduced, the conducting performance of the conducting adhesive film is improved, and the electrical connection between conductors is guaranteed. In addition, the arrangement of the first conducting layer and the second conducting layer also reduces the use of conducting particles, thereby reducing the production cost of the conducting adhesive film and improving the peeling strength of the conducting adhesive film.
In order to solve the same technical problem, the invention also provides another circuit board, which comprises a steel sheet, a printed circuit board and any one of the conductive adhesive films, wherein the steel sheet is laminated with the printed circuit board through the conductive adhesive film; the conductive adhesive layer is electrically connected with the steel sheet, and the protruding part pierces the adhesive layer and is electrically connected with the ground layer of the printed circuit board.
Compared with the prior art, the embodiment of the invention discloses a circuit board, which comprises a steel sheet, a printed circuit board and a conductive adhesive film, wherein when the steel sheet is laminated with the printed circuit board through the conductive adhesive film, the conductive adhesive film can be electrically connected with the steel sheet through the conductive adhesive film layer, and simultaneously, the conductive adhesive film penetrates through the adhesive film layer through the protruding part and is electrically connected with the ground layer of the printed circuit board, so that the reliable connection between the steel sheet and the printed circuit board is realized; meanwhile, the first conducting layer and the second conducting layer are arranged in the conducting adhesive film, so that the overlapping rate of conducting particles in the conducting adhesive film is increased, the problem that the conducting particles are pulled apart due to colloid expansion to increase the resistance of the conducting adhesive film at high temperature can be avoided, the resistance of the conducting adhesive film is greatly reduced, the conducting performance of the conducting adhesive film is improved, and the stability of grounding is guaranteed. In addition, the arrangement of the first conducting layer and the second conducting layer also reduces the use of conducting particles, thereby reducing the production cost of the conducting adhesive film and improving the peeling strength of the conducting adhesive film.
In order to solve the same technical problem, the invention also provides another circuit board, which comprises a steel sheet, a printed circuit board, an electromagnetic shielding film and the conductive adhesive film, wherein the electromagnetic shielding film comprises an insulating layer and a conductor layer which are arranged in a stacked mode, and the electromagnetic shielding film is electrically connected with the ground layer of the printed circuit board through the conductor layer;
the steel sheet is pressed with the electromagnetic shielding film through the conductive adhesive film; the conductive adhesive layer is electrically connected with the steel sheet, and the protruding part pierces the adhesive layer and the insulating layer and is electrically connected with the conductor layer.
Compared with the prior art, the embodiment of the invention discloses a circuit board which comprises a steel sheet, a printed circuit board, an electromagnetic shielding film and a conductive adhesive film, wherein when the steel sheet is pressed with the electromagnetic shielding film through the conductive adhesive film, the conductive adhesive film can be electrically connected with the steel sheet through the conductive adhesive layer, and simultaneously the adhesive film layer and the insulating layer are pierced through by the bulge part and are electrically connected with a conductor layer of the electromagnetic shielding film, so that the reliable connection among the steel sheet, the electromagnetic shielding film and the printed circuit board is realized; meanwhile, the first conducting layer and the second conducting layer are arranged in the conducting adhesive film, so that the overlapping rate of conducting particles in the conducting adhesive film is increased, the problem that the conducting particles are pulled apart due to colloid expansion to increase the resistance of the conducting adhesive film at high temperature can be avoided, the resistance of the conducting adhesive film is greatly reduced, the conducting performance of the conducting adhesive film is improved, and the stability of grounding is guaranteed. In addition, the arrangement of the first conducting layer and the second conducting layer also reduces the use of conducting particles, thereby reducing the production cost of the conducting adhesive film and improving the peeling strength of the conducting adhesive film.
In order to solve the same technical problem, the invention also provides a preparation method of the conductive adhesive film, which is suitable for preparing any one of the conductive adhesive films, and comprises the following steps:
forming a first conductive layer; wherein, a first through hole penetrating through the upper surface and the lower surface of the first conducting layer is formed on the first conducting layer;
forming a resin protrusion at the first through hole; wherein one end of the resin projection extends out of the first through hole;
forming a second conductive layer on one side of the first conductive layer close to the resin bump, and forming a bump at a position where the second conductive layer covers the resin bump;
and forming an adhesive film layer on one side of the second conductive layer, which is far away from the first conductive layer, and forming a conductive adhesive layer on one side of the first conductive layer, which is far away from the second conductive layer.
Preferably, the forming of the resin protrusion at the first through hole includes:
setting resin at the first through hole, and solidifying the resin at a curing temperature after the resin flows from one side to the other side of the first through hole at normal temperature, so as to form the resin protrusion at the first through hole; or the like, or, alternatively,
and arranging resin at the first through hole, and cooling and solidifying the resin after the resin flows from one side to the other side of the first through hole at a melting temperature, thereby forming the resin protrusion at the first through hole.
Preferably, before forming a glue layer on a side of the second conductive layer away from the first conductive layer and forming a conductive glue layer on a side of the first conductive layer away from the second conductive layer, the method further includes the following steps:
forming conductor particles on the outer surface of the protrusion part by one or more processes of physical roughening, chemical plating, physical vapor deposition, chemical vapor deposition, evaporation plating, sputtering plating, electroplating and hybrid plating.
As a preferable scheme, the forming a glue film layer on the side of the second conductive layer far away from the first conductive layer, and forming a conductive glue layer on the side of the first conductive layer far away from the second conductive layer specifically include:
coating a glue film layer on one side of the second conducting layer, which is far away from the first conducting layer, and coating a conductive glue layer on one side of the first conducting layer, which is far away from the second conducting layer;
or coating a glue film layer on a release film, and transferring the glue film layer to one side of the second conductive layer far away from the first conductive layer in a pressing manner;
and coating a conductive adhesive layer on the release film, and transferring the conductive adhesive layer to one side of the first conductive layer, which is far away from the second conductive layer in a pressing manner.
Compared with the prior art, the embodiment of the invention discloses a conductive adhesive film, wherein the resin protrusion is formed at the first through hole of the first conductive layer, and the second conductive layer is formed at one side of the first conductive layer, which is close to the resin protrusion, so that the second conductive layer covers the position of the resin protrusion to form the protrusion part, when conductors are pressed together through the conductive adhesive film, the conductive adhesive film can be electrically connected with one conductor through the conductive adhesive layer, and simultaneously the adhesive film layer is pierced through the protrusion part to be electrically connected with the other conductor, thereby realizing the reliable connection between the conductors; meanwhile, the first conducting layer and the second conducting layer are arranged in the conducting adhesive film, so that the overlapping rate of conducting particles in the conducting adhesive film is increased, the problem that the conducting particles are pulled apart due to expansion of the adhesive body at high temperature to increase the resistance of the conducting adhesive film can be avoided, the resistance of the conducting adhesive film is greatly reduced, the conducting performance of the conducting adhesive film is improved, and the electrical connection between conductors is guaranteed. In addition, the arrangement of the first conducting layer and the second conducting layer reduces the use of conducting particles, reduces the production cost of the conducting adhesive film and improves the peeling strength of the conducting adhesive film.
Drawings
FIG. 1 is a schematic view of a conductive adhesive film according to a first embodiment of the present invention;
FIG. 2 is a cross-sectional view of a conductive adhesive film according to a first embodiment of the present invention;
FIG. 3 is a schematic structural diagram of a conductive adhesive film according to a second embodiment of the present invention;
FIG. 4 is a schematic structural diagram of another conductive adhesive film according to a second embodiment of the present invention;
fig. 5 is a schematic structural diagram of a circuit board in a third embodiment of the present invention;
fig. 6 is a schematic structural diagram of a circuit board in the fourth embodiment of the present invention;
FIG. 7 is a schematic flow chart illustrating a method for manufacturing a conductive adhesive film according to a fifth embodiment of the present invention;
11, a conductive adhesive layer; 111. conductive particles; 12. a first conductive layer; 121. a first through hole; 122. resin bumps; 13. a second conductive layer; 131. a boss portion; 132. a conductive particle; 14. a glue film layer; 15. a first protective film layer; 16. a second protective film layer;
21. a steel sheet; 22. a printed wiring board; 221. a printed wiring board body; 222. an earth formation; 223. a ground hole; 23. an electromagnetic shielding film; 231. an insulating layer; 232. a conductive layer.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Example one
Referring to fig. 1 and 2, a conductive adhesive film according to a preferred embodiment of the present invention includes a conductive adhesive layer 11, a first conductive layer 12, a second conductive layer 13, and an adhesive layer 14;
a first through hole 121 penetrating through the upper and lower surfaces of the first conductive layer 12 is formed in the first conductive layer 12, and a resin protrusion 1312 is formed at the first through hole 121; the second conductive layer 13 is disposed on one side of the first conductive layer 12 close to the resin bump 1312, and a bump 131 is formed at a position where the second conductive layer 13 covers the resin bump 1312; the adhesive layer 14 is arranged on one surface of the second conductive layer 13 far away from the first conductive layer 12, and the conductive adhesive layer 11 is arranged on one surface of the first conductive layer 12 far away from the second conductive layer 13; wherein the resin protrusion 1312 is formed by solidifying the resin after flowing from one side to the other side of the first through hole 121.
In the embodiment of the present invention, by sequentially disposing the conductive adhesive layer 11, the first conductive layer 12, the first conductive layer 13 and the adhesive layer 14, disposing the resin protrusion 122 at the first through hole 121 of the first conductive layer 12, and forming the protrusion 131 at the position where the second conductive layer 13 covers the resin protrusion 122, when the conductors are laminated by the conductive adhesive film, the conductive adhesive film can be electrically connected to one of the conductors by the conductive adhesive layer 11, and the adhesive layer 14 is pierced by the protrusion 131 to be electrically connected to the other conductor, thereby realizing reliable connection between the conductors; meanwhile, the first conductive layer 12 and the second conductive layer 13 which are arranged in the conductive adhesive film increase the overlapping rate of conductive particles in the conductive adhesive film, and can avoid the problem that the resistance of the conductive adhesive film is increased due to the fact that the conductive particles are pulled apart due to expansion of the adhesive body at high temperature, so that the resistance of the conductive adhesive film is greatly reduced, the conductive performance of the conductive adhesive film is improved, and the electrical connection between conductors is guaranteed. In addition, the conductive adhesive layer 11 in this embodiment includes conductive particles 111; however, compared with the conventional conductive adhesive film, in the embodiment, due to the arrangement of the first conductive layer 12 and the second conductive layer 13, the use of conductive particles is greatly reduced, so that the production cost of the conductive adhesive film is reduced, and the peel strength of the conductive adhesive film is improved.
In one preferred mode of the present invention, the process of forming the resin protrusion 122 is embodied as: the resin protrusion 122 is formed by instantly cooling and solidifying after resin flows from one side of the first through hole 121 close to the conductive adhesive layer 11 to the other side at a melting temperature. In another preferred embodiment, the resin is a curing adhesive, and the forming process of the resin protrusion 122 is embodied as follows: at normal temperature, liquefied resin is solidified at a curing temperature after flowing from one side of the first through hole 121 close to the conductive adhesive layer 11 to the other side. The resin forming the resin protrusion 122 may be provided at one end of the first through hole 121 far from the second conductive layer 13, or may be provided on one surface of the first conductive layer 12 far from the second conductive layer 13; the resin may be a thermoplastic resin or a thermosetting resin.
In the embodiment of the present invention, it should be noted that the structure of the resin protrusion 122 shown in the drawings is merely exemplary. Since the resin protrusion 122 is formed by the resin being solidified after flowing from one side to the other side of the first through-hole 121, in either case, the resin flows out almost completely from the first through-hole 121 without remaining in the first through-hole 121, and thus the resin protrusion 122 can be formed as shown in the drawing, the resin protrusion 122 being formed at the boundary of the first through-hole 11 and the second conductor layer 2; in another case, resin remains in the first through hole 121, and the first through hole 121 is even filled with resin, so that one end of the resin projection 122 is formed to be located in the first through hole 121 and the other end of the resin projection 122 protrudes out of the first through hole 121; in still another case, a resin remains on a surface of the first conductor layer 1 on a side away from the second conductor layer 2, and therefore, the resin bump 122 may be formed to penetrate the first through hole 11. The resin protrusion 122 of the present invention is not limited to the shape shown in the drawings, and any resin protrusion having piercing ability is within the scope of the present invention.
In the embodiment of the present invention, in order to ensure that the resin bump 122 can be formed at the first through hole 121 while ensuring that the first conductive layer 12 is not easily broken, it is preferable that the cross-sectional area of the first through hole 121 in the embodiment is 0.01 μm
2-1mm
2。
In addition, in order to ensure that enough resin bumps 122 can be formed on the first conductive layer 12 to ensure that the bumps 131 formed on the second conductive layer 13 can smoothly penetrate through the adhesive film layer 14 and ensure that the first conductive layer 12 is not easily broken, the number of the first through holes 121 in the first conductive layer 12 per square centimeter is 5-10 in the present embodiment
10And (4) respectively. Accordingly, the number of the resin bumps 122 per square centimeter of the first conductor layer 12 is 5 to 10
10A plurality of; it should be noted that, since the second conductive layer 13 covers the resin bumps 122, the protrusions 131 are formed on the outer surface of the second conductive layer 13 at positions corresponding to the resin bumps 122, and therefore, the number of the protrusions 131 corresponds to the number of the resin bumps 122, thereby ensuring that the adhesive film layer 14 can be smoothly pierced.
In the embodiment of the present invention, the first through holes 121 may be regularly or irregularly distributed on the first conductive layer 12; wherein, the first through holes 121 are regularly distributed on the first conductive layer 12, which means that the shapes of the first through holes 121 are the same and are uniformly distributed on the first conductive layer 12; the first through holes 121 are irregularly distributed on the first conductive layer 12, that is, the first through holes 121 have different shapes and are irregularly distributed on the first conductive layer 12. Preferably, the first through holes 121 have the same shape, and the first through holes 121 are uniformly distributed on the first conductive layer 12, as shown in fig. 2. In addition, the first through hole 121 may be a circular through hole, and may also be a through hole of any other shape, and the drawings of the present invention only illustrate that the first through hole 121 is a circular through hole, but the first through hole 121 of any other shape is within the scope of the present invention.
In the embodiment of the present invention, the shape of the protrusion 131 may be the same as the shape of the resin protrusion 122, or may be different from the shape of the resin protrusion 122, and the shape of the protrusion 131 shown in the drawings is merely exemplary.
In the embodiment of the present invention, the thickness of the first conductive layer 12 is preferably 0.1 μm to 45 μm; the thickness of the second conductive layer 13 is preferably 0.1 μm to 45 μm, thereby ensuring that the first conductive layer 12 and the second conductive layer 13 are not easily broken and have good flexibility. In addition, in order to ensure that the first conductive layer 12 and the second conductive layer 13 have good conductivity, the first conductive layer 12 includes one or more of a metal conductive layer, a carbon nanotube conductive layer, a ferrite conductive layer, and a graphene conductive layer; the second conductive layer 13 includes one or more of a metal conductive layer, a carbon nanotube conductive layer, a ferrite conductive layer, and a graphene conductive layer. Wherein the metal conductive layer comprises a single metal conductive layer and/or an alloy conductive layer; the single metal conducting layer is made of any one of aluminum, titanium, zinc, iron, nickel, chromium, cobalt, copper, silver and gold, and the alloy conducting layer is made of any two or more of aluminum, titanium, zinc, iron, nickel, chromium, cobalt, copper, silver and gold.
In the embodiment of the present invention, the first conductive layer 12 includes a first surface and a second surface which are oppositely arranged, and the first surface is in contact with the second conductive layer 13; the second surface is in contact with the conductive glue layer 11. It should be noted that both the first surface and the second surface may be surfaces of any shape, for example, they may be flat surfaces as shown in fig. 1, or may be uneven surfaces with undulations, or other rough surfaces; in addition, the first surface and the second surface may be regular surfaces or irregular surfaces. The drawings of the present invention are only for illustrating that the first surface and the second surface are flat surfaces, and any other shapes of the first surface and the second surface are within the protection scope of the present invention. In addition, a surface of the second conductive layer 13 contacting the first surface may also be a surface of any shape, for example, a flat surface as shown in fig. 1, a non-flat surface with a wavy shape, or other rough surfaces, which will not be described herein.
In the embodiment of the present invention, it should be noted that, in the drawings of the present embodiment, both the first conductive layer 12 and the second conductive layer 13 may have a single-layer structure, or may have a multi-layer structure. In addition, the first conductive layer 12 and the second conductive layer 13 of the present embodiment can be arranged in a grid shape, a foaming shape, etc. according to the requirements of actual production and application.
In the embodiment of the present invention, one of the structures of the adhesive film layer 14 is specifically represented as: the glue film layer 14 includes an adhesive layer containing conductive particles. By making the glue film layer 14 include an adhesion layer containing conductive particles, the glue film layer 14 not only has an adhesion function to make the conductive glue film and the conductor tightly adhere, but also the glue film layer 14 has a conductive function, which is matched with the second conductive layer 13 and the first conductive layer 12 to ensure the electrical connection between the conductors. The conductive particles can be mutually separated conductive particles or aggregated large-particle conductive particles; when the conductive particles are mutually separated, the area of electrical contact can be further increased, and the uniformity of the electrical contact is improved; and when the conductive particles are large agglomerated conductive particles, the piercing strength can be increased.
In the embodiment of the present invention, another structure of the adhesive film layer 14 is specifically represented as follows: the glue film layer 14 includes an adhesive layer that does not contain conductive particles. The adhesive film layer 14 has an adhesive effect by including the adhesive layer without containing conductive particles, and the adhesive film layer 14 includes the adhesive layer without containing conductive particles, so that the insertion loss in the using process is reduced, and the bending property of the conductive adhesive film is improved.
In the embodiment of the present invention, the thickness of the adhesive film layer 14 is 0.1 μm to 60 μm. The glue film layer 14 is made of the following materials: modified epoxy resins, acrylic resins, modified rubbers, and modified thermoplastic polyimides. In addition, the outer surface of the adhesive film layer 14 may be a flat surface without undulation, or may be a non-flat surface with gentle undulation.
In the embodiment of the present invention, in order to avoid contamination from impurities such as external dust, the conductive adhesive film in this embodiment further includes a first protective film layer 15 and a second protective film layer 16, where the first protective film layer 15 is disposed on a surface of the adhesive film layer 14 away from the second conductive layer 13; the second protective film layer 16 is disposed on a surface of the conductive adhesive layer 11 away from the first conductive layer 12. When the conductive adhesive film is used, the first protective film layer 15 and the second protective film layer 16 need to be peeled off.
In addition, the first protective film layer 15 and the second protective film layer 16 respectively include a PPS film layer, a PEN film layer, a polyester film layer, a polyimide film layer, a film layer formed after curing epoxy resin ink, a film layer formed after curing polyurethane ink, a film layer formed after curing modified acrylic resin, or a film layer formed after curing polyimide resin.
Example two
As shown in fig. 3 and 4, the difference between the conductive adhesive film in the present embodiment and the first embodiment is that the surface of the protrusion 131 is provided with conductive particles 132. By arranging the conductor particles 132 on the surface of the protrusion 131, the piercing strength of the protrusion 131 is enhanced, and it is further ensured that the protrusion 131 can pierce the adhesive film layer 14 smoothly in the pressing process.
Preferably, the conductive particles 132 are concentrated on the outwardly protruding positions of the surface of the protrusion 131, so that the adhesive film layer 14 can be easily pierced. Of course, the non-convex portions of the surface of the convex portion 131 may have the conductive particles 132 distributed. In addition, the conductor particles 132 may also be distributed on other positions of the second conductive layer 13 near the surface of the adhesive film layer 14, not only on the surface of the protrusion 131, as shown in fig. 3 and 4. Of course, the conductive particles 132 may also be distributed only on the protrusions 131.
In a specific implementation, as shown in fig. 3, the second conductive layer 13 may be formed first, and then the conductive particles 132 may be formed on a side of the second conductive layer 13 away from the first conductive layer 13 by another process. Of course, the second conductive layer 13 and the conductive particles 132 may be an integral structure formed by a one-step molding process, as shown in fig. 4.
In the embodiment of the present invention, the conductive particles 132 may be spaced from the outer surface of the adhesive film layer 14, and may contact the outer surface of the adhesive film layer 14 or extend out of the outer surface of the adhesive film layer 14.
In order to ensure the piercing strength of the protrusion 131 to ensure that the protrusion 131 can pierce the adhesive film layer 14, the height of the conductive particle 132 is preferably 1 μm to 30 μm.
In an embodiment of the present invention, the conductor particles 132 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; the single metal particles are made of any one of aluminum, titanium, zinc, iron, nickel, chromium, cobalt, copper, silver and gold, and the alloy particles are made of any two or more of aluminum, titanium, zinc, iron, nickel, chromium, cobalt, copper, silver and gold. In addition, the conductive particles 132 may be the same as or different from the material of the second conductive layer 13.
In the embodiment of the present invention, it should be noted that the shape of the conductor particles 132 as shown in fig. 3 and fig. 4 is only an example, and due to differences in process means and parameters, the conductor particles 132 may also be in other shapes such as clusters, ice-hanging shapes, stalactite shapes, and dendrites. In addition, the conductive particles 132 of the present invention are not limited to the shapes shown in the drawings and described above, and any conductive particles having piercing and conductive functions are within the scope of the present invention.
In the embodiment of the present invention, in order to further ensure the piercing strength of the protrusion 131, it is preferable that the conductive particles 132 are plural. A plurality of the conductor particles 132 may be regularly or irregularly distributed on the surface of the convex portion 131; the plurality of conductor particles 132 may also be continuously or discontinuously distributed on the surface of the protrusion 131. Wherein, the plurality of conductor particles 132 are regularly distributed on the surface of the protrusion 131 means that the plurality of conductor particles 132 are uniformly distributed on the surface of the protrusion 131; the plurality of conductor particles 132 irregularly distributed on the surface of the protrusion 131 means that the plurality of conductor particles 132 are irregularly shaped and irregularly distributed on the surface of the protrusion 131. In addition, the sizes of the plurality of conductor particles 132 may also be set according to actual use conditions, for example, the sizes of the plurality of conductor particles 132 are set to be the same, and certainly, the sizes of the plurality of conductor particles 132 may also be set to be different, which is not described herein further.
In addition, other structures and working principles of the conductive adhesive film of the present embodiment are the same as those of the first embodiment, and are not further described herein.
EXAMPLE III
As shown in fig. 5, an embodiment of the present invention provides a wiring board including a steel sheet 21 and a printed wiring board 22; the circuit board further comprises the conductive adhesive film of the first embodiment or the second embodiment, and the steel sheet 21 is pressed with the printed circuit board 22 through the conductive adhesive film; the conductive adhesive layer 11 is electrically connected with the steel sheet 21, and the protruding portion 131 pierces the adhesive layer 14 and is electrically connected with the ground layer 222 of the printed circuit board 22.
Specifically, the printed wiring board 22 includes a printed wiring board body 221 and a ground layer 222 which are stacked, and a ground hole 223 is formed in the printed wiring board body 221; therefore, the protruding portion 131 pierces through the adhesive film layer 13 and is electrically connected to the ground layer 222 of the printed circuit board 22, specifically: the protrusions 131 pierce the adhesive film layer 13 and pass through the grounding hole 223, thereby electrically connecting with the ground layer 222 of the printed wiring board 22.
In the embodiment of the present invention, it should be noted that the protruding portions 131 on the conductive film may all contact with the ground layer 222 of the printed circuit board 22, or may partially contact with the ground layer 222 of the printed circuit board 22. It can be understood that the number of the grounding holes 223 can be set according to the actual use condition, and only needs to be enough to ensure that the conductive film is effectively connected with the ground layer 222 of the printed circuit board 22.
In addition, the circuit board further comprises an electromagnetic shielding film 23, and the electromagnetic shielding film 23 is arranged on the position, where the conductive adhesive film is not arranged, of the printed circuit board 22. Specifically, the electromagnetic shielding film 23 includes an insulating layer 231 and a conductor layer 232, which are stacked, the conductor layer 232 is disposed on the printed wiring board body 221, and a conductor layer convex portion extending in a direction close to the ground hole 223 is disposed on a position of the conductor layer 232 opposite to the ground hole 223, and the conductor layer convex portion passes through the ground hole 223 and is electrically connected to the ground layer 222 of the printed wiring board 22.
In the embodiment of the present invention, in order to secure the reinforcing effect of the steel sheet 21, the thickness of the steel sheet is preferably 0.05mm to 0.2 mm; in addition, the material of the steel sheet 21 may be set according to actual use conditions, and in the embodiment, the steel sheet 21 is preferably a nickel-plated steel sheet.
In the embodiment of the invention, due to the arrangement of the steel sheet 21, the stiffness of the circuit board is enhanced, and the phenomenon that the installation part of the circuit board is deformed due to bending and the like can be effectively prevented, so that the operation of installing and carrying printed circuit board parts and the like is facilitated; meanwhile, under the matching of the conductive adhesive film and the steel sheet 21, the circuit board has good grounding stability, interference charges in the circuit board can be effectively led out, and the effect of effectively shielding external electromagnetic wave interference can be realized.
In a specific implementation, when the circuit board is applied to an electronic device, the steel sheet 21 may be connected to a housing of the electronic device, so that the interference charges accumulated in the circuit board are conducted out by the cooperation of the steel sheet 21 and the conductive adhesive film.
In addition, in this embodiment, reference may be made to the description of the first embodiment and the second embodiment for the implementation of the conductive adhesive film, and details are not repeated herein.
In the embodiment of the present invention, the printed wiring board 22 is preferably one of a flexible single board, a flexible double-sided board, a flexible multilayer board, and a rigid-flex printed board.
In the embodiment of the invention, the reliable connection between the steel sheet and the printed circuit board is realized through the structure; meanwhile, the first conducting layer and the second conducting layer are arranged in the conducting adhesive film, so that the overlapping rate of conducting particles in the conducting adhesive film is increased, the problem that the conducting particles are pulled apart due to colloid expansion to increase the resistance of the conducting adhesive film at high temperature can be avoided, the resistance of the conducting adhesive film is greatly reduced, the conducting performance of the conducting adhesive film is improved, and the stability of grounding is guaranteed. In addition, the arrangement of the first conducting layer and the second conducting layer also reduces the use of conducting particles, thereby reducing the production cost of the conducting adhesive film and improving the peeling strength of the conducting adhesive film.
Example four
As shown in fig. 6, another circuit board according to an embodiment of the present invention includes a steel sheet 21, a printed circuit board 22, and an electromagnetic shielding film 23, where the electromagnetic shielding film 23 includes an insulating layer 231 and a conductor layer 232 that are stacked, and the electromagnetic shielding film 23 is electrically connected to a ground layer 222 of the printed circuit board 22 through the conductor layer 232;
the circuit board further comprises the conductive adhesive film of the first embodiment or the second embodiment, and the steel sheet 21 is pressed with the electromagnetic shielding film 23 through the conductive adhesive film; the conductive adhesive layer 11 is electrically connected to the steel sheet 21, and the protrusion 131 pierces through the adhesive layer 13 and the insulating layer 231 and is electrically connected to the conductor layer 232.
The electromagnetic shielding film 23 is electrically connected to the ground layer 222 of the printed circuit board 22 through the conductor layer 232, which is specifically represented as: the printed circuit board 22 comprises a printed circuit board body 221 and a ground layer 222 which are arranged in a stacked mode, and a grounding hole 223 is formed in the printed circuit board body 221; the conductor layer 232 is disposed on the printed wiring board body 221, and a conductor layer convex portion extending in a direction close to the ground hole 223 is disposed on a position of the conductor layer 232 opposite to the ground hole 223, and the conductor layer convex portion passes through the ground hole 223, thereby being electrically connected to the ground layer 222 of the printed wiring board 22.
In the embodiment of the present invention, the conductive adhesive layer 11 is electrically connected to the steel sheet 21, and the protrusion 131 penetrates through the adhesive film layer 13 and the insulating layer 231 to be electrically connected to the conductor layer 232, so that the steel sheet 21 can be electrically connected to the second conductive adhesive film layer 232 of the electromagnetic shielding film 23 through the conductive adhesive film, and thus, the electrical connection with the ground layer 222 of the printed circuit board 22 is achieved.
The protrusions 161 on the conductive adhesive film may be all in contact with the conductive layer 232, or may be partially in contact with the conductive layer 232.
In the embodiment of the present invention, in order to secure the reinforcing effect of the steel sheet 21, the thickness of the steel sheet is preferably 0.05mm to 0.2 mm; in addition, the material of the steel sheet 21 may be set according to actual use conditions, and in the embodiment, the steel sheet 21 is preferably a nickel-plated steel sheet.
In the embodiment of the invention, due to the arrangement of the steel sheet 21, the stiffness of the circuit board is enhanced, and the phenomenon that the installation part of the circuit board is deformed due to bending and the like can be effectively prevented, so that the operation of installing and carrying printed circuit board parts and the like is facilitated; meanwhile, under the matching of the conductive adhesive film and the steel sheet 21, the circuit board has good grounding stability, interference charges in the circuit board can be effectively led out, and the effect of effectively shielding external electromagnetic wave interference can be realized.
In a specific implementation, when the circuit board is applied to an electronic device, the interference charges accumulated in the circuit board can be conducted out by electrically connecting the steel sheet 21 with a housing of the electronic device under the cooperation of the steel sheet 21 and the conductive adhesive film.
In addition, in this embodiment, reference may be made to the description of the first embodiment and the second embodiment for the implementation of the conductive adhesive film, and details are not repeated herein.
In the embodiment of the present invention, the printed wiring board 7 is preferably one of a flexible single-sided board, a flexible double-sided board, a flexible multilayer board, and a rigid-flex printed board.
In the embodiment of the invention, the reliable connection between the steel sheet and the printed circuit board is realized through the structure; meanwhile, the first conductive layer 12 and the second conductive layer 13 arranged in the conductive adhesive film increase the overlapping rate of conductive particles in the conductive adhesive film, and can avoid the problem that the resistance of the conductive adhesive film is increased due to the fact that the conductive particles are pulled apart due to expansion of the adhesive body at high temperature, so that the resistance of the conductive adhesive film is greatly reduced, the conductive performance of the conductive adhesive film is improved, and the stability of grounding is guaranteed. In addition, the arrangement of the first conductive layer 12 and the second conductive layer 13 also reduces the use of conductive particles, thereby reducing the production cost of the conductive adhesive film and improving the peel strength of the conductive adhesive film.
EXAMPLE five
As shown in fig. 7, an embodiment of the present invention provides a method for preparing a conductive adhesive film, which is suitable for preparing the conductive adhesive film described in the first embodiment, and includes steps S11 to S13:
s11, forming a first conductive layer; wherein, a first through hole penetrating through the upper surface and the lower surface of the first conducting layer is formed on the first conducting layer;
in the embodiment of the present invention, preferably, the cross-sectional area of the first through-hole is 0.01 μm
2-1mm
2(ii) a The number of the first through holes in the first conductive layer per square centimeter is 5-10
6And (4) respectively.
S12, forming a resin bulge at the first through hole; wherein one end of the resin projection extends out of the first through hole;
wherein the forming of the resin protrusion at the first through hole is specifically:
and arranging resin at the first through hole, and solidifying the resin after the resin flows from one side to the other side of the first through hole, so that a resin bulge is formed at the first through hole.
Specifically, in one of preferred modes, after a resin is provided at the first through hole and is caused to flow from one side to the other side of the first through hole at normal temperature, the resin is solidified at a curing temperature, thereby forming a resin protrusion at the first through hole; in yet another preferred embodiment, a resin is provided at the first through-hole and instantaneously cooled after flowing from one side to the other side of the first through-hole at a melting temperature, thereby forming a resin protrusion at the first through-hole.
S13, forming a second conductive layer on one side of the first conductive layer close to the resin bump, and forming a bump at the position where the second conductive layer covers the resin bump;
and S14, forming an adhesive film layer on one side of the second conductive layer far away from the first conductive layer, and forming a conductive adhesive layer on one side of the first conductive layer far away from the second conductive layer.
Specifically, in a preferred mode, a glue film layer is coated on a release film, and the glue film layer is transferred to one side, away from the first conductive layer, of the second conductive layer in a pressing mode;
and coating a conductive adhesive layer on the release film, and transferring the conductive adhesive layer to one side of the first conductive layer, which is far away from the second conductive layer in a pressing manner.
In another preferred mode, a glue film layer is coated on one side of the second conductive layer, which is far away from the first conductive layer, and a conductive glue layer is coated on one side of the first conductive layer, which is far away from the second conductive layer.
In another preferred embodiment suitable for preparing the adhesive conductive film of the second embodiment, after step S13 and before step S14, the method further comprises the steps of:
forming conductor particles on the outer surface of the protrusion part by one or more processes of physical roughening, chemical plating, physical vapor deposition, chemical vapor deposition, evaporation plating, sputtering plating, electroplating and hybrid plating.
In the embodiment of the invention, the resin protrusion is formed at the first through hole of the first conductive layer, and the second conductive layer is formed on the side of the first conductive layer close to the resin protrusion, so that the second conductive layer covers the resin protrusion to form the protrusion, when the conductors are pressed together through the conductive adhesive film, the conductive adhesive film can be electrically connected with one conductor through the conductive adhesive layer, and simultaneously the adhesive film layer is pierced through by the protrusion to be electrically connected with the other conductor, thereby realizing reliable connection between the conductors. The first conducting layer and the second conducting layer in the conducting adhesive film increase the overlapping rate of conducting particles in the conducting adhesive film, and can avoid the problem that the conducting particles are pulled apart due to the expansion of colloid to increase the resistance of the conducting adhesive film at high temperature, so that the resistance of the conducting adhesive film is greatly reduced, the conducting performance of the conducting adhesive film is improved, and the electrical connection between conductors is ensured. In addition, the arrangement of the first conducting layer and the second conducting layer reduces the use of conducting particles, reduces the production cost of the conducting adhesive film and improves the peeling strength of the conducting adhesive film.
The above description is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, various modifications and substitutions can be made without departing from the technical principle of the present invention, and these modifications and substitutions should also be regarded as the protection scope of the present invention.
Claims (16)
1. A conductive adhesive film is characterized by comprising a conductive adhesive layer, a first conductive layer, a second conductive layer and an adhesive film layer;
the first conducting layer is provided with a first through hole penetrating through the upper surface and the lower surface of the first conducting layer, and a resin bulge is arranged at the first through hole; the second conducting layer is arranged on one side, close to the resin bulge, of the first conducting layer, and a bulge part is formed at the position, covered by the second conducting layer, of the resin bulge; the adhesive film layer is arranged on one surface, far away from the first conducting layer, of the second conducting layer, and the conductive adhesive layer is arranged on one surface, far away from the second conducting layer, of the first conducting layer; wherein the resin protrusion is formed by solidification of resin after flowing from one side to the other side of the first through hole.
2. The conductive adhesive film according to claim 1, wherein the resin protrusion is formed by solidifying at a curing temperature after resin flows from one side to the other side of the first through hole at a normal temperature; or the like, or, alternatively,
the resin protrusion is formed by cooling and solidifying after resin flows from one side to the other side of the first through hole at a melting temperature.
3. The conductive adhesive film according to claim 1, wherein the surface of the protrusion is provided with conductive particles; the height of the conductor particles is 1-30 μm.
4. The conductive adhesive film according to claim 3, wherein the conductive particles have a cluster shape, an ice-hanging shape, a stalactite shape, or a dendritic shape.
5. The conductive adhesive film according to claim 3, wherein the conductive particles are plural; a plurality of conductor particles are regularly or irregularly distributed on the surface of the convex part; the plurality of conductor particles are continuously or discontinuously distributed on the surface of the convex part.
6. The conductive adhesive film of claim 1, wherein the adhesive layer comprises an adhesive layer containing conductive particles; or the adhesive film layer comprises an adhesion layer without conductive particles.
7. The conductive adhesive film according to any one of claims 1 to 6, wherein the first conductive layer and the second conductive layer respectively comprise one or more of a metal conductive layer, a carbon nanotube conductive layer, a ferrite conductive layer, and a graphene conductive layer.
8. The conductive adhesive film according to claim 7, wherein the metal conductive layer comprises a single metal conductive layer and/or an alloy conductive layer; the single metal conducting layer is made of any one of aluminum, titanium, zinc, iron, nickel, chromium, cobalt, copper, silver and gold, and the alloy conducting layer is made of any two or more of aluminum, titanium, zinc, iron, nickel, chromium, cobalt, copper, silver and gold.
9. The conductive adhesive film according to any one of claims 1 to 6, wherein the number of the first through holes in the first conductive layer per square centimeter is 10 to 1000; and/or the cross-sectional area of the first through hole is 0.1 mu m
2-1mm
2。
10. The adhesive conductive film of any one of claims 1-6, further comprising a first protective film layer and a second protective film layer, wherein the first protective film layer is disposed on a side of the adhesive film layer away from the second conductive layer; the second protective film layer is arranged on one surface, far away from the first conductive layer, of the conductive adhesive layer.
11. A wiring board comprising a steel sheet, a printed wiring board, and the conductive film according to any one of claims 1 to 10, wherein the steel sheet is laminated with the printed wiring board via the conductive film; the conductive adhesive layer is electrically connected with the steel sheet, and the protruding part pierces the adhesive layer and is electrically connected with the ground layer of the printed circuit board.
12. A circuit board comprising a steel sheet, a printed wiring board, an electromagnetic shielding film and the conductive adhesive film according to any one of claims 1 to 10, wherein the electromagnetic shielding film comprises an insulating layer and a conductor layer which are stacked, and the electromagnetic shielding film is electrically connected with a ground layer of the printed wiring board through the conductor layer;
the steel sheet is pressed with the electromagnetic shielding film through the conductive adhesive film; the conductive adhesive layer is electrically connected with the steel sheet, and the protruding part pierces the adhesive layer and the insulating layer and is electrically connected with the conductor layer.
13. A method for preparing an adhesive conductive film, suitable for preparing the adhesive conductive film according to any one of claims 1-10, comprising the steps of:
forming a first conductive layer; wherein, a first through hole penetrating through the upper surface and the lower surface of the first conducting layer is formed on the first conducting layer;
forming a resin protrusion at the first through hole; wherein one end of the resin projection extends out of the first through hole;
forming a second conductive layer on one side of the first conductive layer close to the resin bump, and forming a bump at a position where the second conductive layer covers the resin bump;
and forming an adhesive film layer on one side of the second conductive layer, which is far away from the first conductive layer, and forming a conductive adhesive layer on one side of the first conductive layer, which is far away from the second conductive layer.
14. The method of claim 13, wherein forming a resin protrusion at the first through hole comprises:
setting resin at the first through hole, and solidifying the resin at a curing temperature after the resin flows from one side to the other side of the first through hole at normal temperature, so as to form the resin protrusion at the first through hole;
or, after resin is provided at the first through hole and is caused to flow from one side to the other side of the first through hole at a melting temperature, the resin is solidified by cooling, thereby forming the resin protrusion at the first through hole.
15. The method of claim 13, wherein before forming the adhesive layer on the side of the second conductive layer away from the first conductive layer and forming the conductive adhesive layer on the side of the first conductive layer away from the second conductive layer, the method further comprises:
forming conductor particles on the outer surface of the protrusion part by one or more processes of physical roughening, chemical plating, physical vapor deposition, chemical vapor deposition, evaporation plating, sputtering plating, electroplating and hybrid plating.
16. The method for preparing a conductive adhesive film according to claim 13, wherein the step of forming an adhesive film layer on the side of the second conductive layer away from the first conductive layer and forming a conductive adhesive layer on the side of the first conductive layer away from the second conductive layer comprises:
coating a glue film layer on one side of the second conducting layer, which is far away from the first conducting layer, and coating a conductive glue layer on one side of the first conducting layer, which is far away from the second conducting layer;
or coating a glue film layer on a release film, and transferring the glue film layer to one side of the second conductive layer far away from the first conductive layer in a pressing manner;
and coating a conductive adhesive layer on the release film, and transferring the conductive adhesive layer to one side of the first conductive layer, which is far away from the second conductive layer in a pressing manner.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811423719.0A CN110783017B (en) | 2018-11-26 | 2018-11-26 | Conductive adhesive film, circuit board and preparation method of conductive adhesive film |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811423719.0A CN110783017B (en) | 2018-11-26 | 2018-11-26 | Conductive adhesive film, circuit board and preparation method of conductive adhesive film |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN110783017A true CN110783017A (en) | 2020-02-11 |
| CN110783017B CN110783017B (en) | 2024-03-19 |
Family
ID=69383213
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201811423719.0A Active CN110783017B (en) | 2018-11-26 | 2018-11-26 | Conductive adhesive film, circuit board and preparation method of conductive adhesive film |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN110783017B (en) |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101909405A (en) * | 2007-12-11 | 2010-12-08 | 住友电木株式会社 | The manufacture method of circuit board, circuit board and coverlay |
| US20150030878A1 (en) * | 2012-06-21 | 2015-01-29 | Guangzhou Fang Bang Electronics Co., Ltd. | Ultrathin shielding film of high shielding effectiveness and manufacturing method thereof |
| CN209461175U (en) * | 2018-11-26 | 2019-10-01 | 广州方邦电子股份有限公司 | Conductive adhesive film and wiring board |
-
2018
- 2018-11-26 CN CN201811423719.0A patent/CN110783017B/en active Active
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101909405A (en) * | 2007-12-11 | 2010-12-08 | 住友电木株式会社 | The manufacture method of circuit board, circuit board and coverlay |
| US20150030878A1 (en) * | 2012-06-21 | 2015-01-29 | Guangzhou Fang Bang Electronics Co., Ltd. | Ultrathin shielding film of high shielding effectiveness and manufacturing method thereof |
| CN209461175U (en) * | 2018-11-26 | 2019-10-01 | 广州方邦电子股份有限公司 | Conductive adhesive film and wiring board |
Also Published As
| Publication number | Publication date |
|---|---|
| CN110783017B (en) | 2024-03-19 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN108323144B (en) | Electromagnetic shielding film, circuit board and preparation method of electromagnetic shielding film | |
| JP4974803B2 (en) | Shield film for printed wiring board and printed wiring board | |
| CN110783022B (en) | Conductive adhesive film, circuit board and preparation method of conductive adhesive film | |
| JP2009038278A5 (en) | ||
| CN209947452U (en) | Conductive adhesive film and circuit board | |
| CN209947454U (en) | Conductive adhesive film and circuit board | |
| CN209461175U (en) | Conductive adhesive film and wiring board | |
| CN110784984A (en) | Free grounding film, circuit board and preparation method of free grounding film | |
| CN110769665B (en) | Electromagnetic shielding film, circuit board and preparation method of electromagnetic shielding film | |
| CN110783017B (en) | Conductive adhesive film, circuit board and preparation method of conductive adhesive film | |
| CN110769667B (en) | Electromagnetic shielding film, circuit board and preparation method of electromagnetic shielding film | |
| CN209947456U (en) | Conductive adhesive film and circuit board | |
| CN110784983A (en) | Free grounding film, circuit board and preparation method of free grounding film | |
| CN209947455U (en) | Conductive adhesive film and circuit board | |
| CN110784986A (en) | Free grounding film, circuit board and preparation method of free grounding film | |
| CN110784993A (en) | Free grounding film, circuit board and preparation method of free grounding film | |
| CN110769586A (en) | Electromagnetic shielding film, circuit board and preparation method of electromagnetic shielding film | |
| CN110769664B (en) | Electromagnetic shielding film, circuit board and preparation method of electromagnetic shielding film | |
| CN110769668B (en) | Electromagnetic shielding film, circuit board and preparation method of electromagnetic shielding film | |
| CN110769670B (en) | Electromagnetic shielding film, circuit board and preparation method of electromagnetic shielding film | |
| CN110783015A (en) | Conductive adhesive film, circuit board and preparation method of conductive adhesive film | |
| CN110783016A (en) | Conductive adhesive film, circuit board and preparation method of conductive adhesive film | |
| CN110784989A (en) | Free grounding film, circuit board and preparation method of free grounding film | |
| CN110797137A (en) | Conductive adhesive film, circuit board and preparation method of conductive adhesive film | |
| CN110769668A (en) | Electromagnetic shielding film, circuit board and preparation method of electromagnetic shielding film |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |