Adhesive film for circuit connection and method for manufacturing the same, and connection structure and method for manufacturing the same

Abstract

A method of manufacturing an adhesive film for circuit connection, the method comprising: preparing a substrate having a plurality of recesses on a surface thereof and having conductive particles in at least a portion of the plurality of recesses; providing, on the surface of the substrate, a composition layer containing a photosetting component and a first thermosetting component to transfer the conductive particles to the composition layer; irradiating the composition layer with light to form a first adhesive layer containing the conductive particles, a cured product of the photosetting component, and the first thermosetting component; and providing, on one surface of the first adhesive layer, a second adhesive layer containing a second thermosetting component.

Claims

1. A substrate is prepared having a plurality of recesses on its surface, in which solder particles are arranged in at least a portion of the plurality of recesses. A composition layer containing a photocurable component having radical curability and a first thermosetting component not having radical curability is provided on the surface of the substrate, thereby transferring the solder particles to the composition layer. By irradiating the composition layer with light, a first adhesive layer containing a plurality of solder particles, a cured product of the photocurable component, and the first thermosetting component is formed. A method for manufacturing an adhesive film for circuit connections, comprising providing a second adhesive layer containing a second thermosetting component on one surface of the first adhesive layer.

2. The photocurable component comprises a radical polymerizable compound and a photoradical polymerization initiator. A method for producing an adhesive film for circuit connections according to claim 1, wherein the first thermosetting component comprises a cationic polymerizable compound and a thermal cationic polymerization initiator.

3. The method for producing a circuit connection adhesive film according to claim 2, wherein the first thermosetting component includes a compound having a cyclic ether group as the cationic polymerizable compound.

4. The method for producing a circuit connection adhesive film according to claim 3, wherein the first thermosetting component includes at least one selected from the group consisting of oxetane compounds and alicyclic epoxy compounds as the cationic polymerizable compound.

5. A method for producing an adhesive film for circuit connections according to any one of claims 2 to 4, wherein the photocurable component includes a compound represented by the following formula (1) as the radical polymerizable compound. 【Chemistry 1】 [In formula (1), R １ represents a hydrogen atom or a methyl group, and X represents an alkanediyl group having 1 to 3 carbon atoms.

6. A method for producing an adhesive film for circuit connections according to any one of claims 2 to 5, wherein the photocurable component includes a compound represented by the following formula (I) as the photoradical polymerization initiator. 【Chemistry 2】 [In formula (I), R ２ , R ３ and R ４ Each of these independently represents an organic group containing a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, or an aromatic hydrocarbon group.

7. A method for producing an adhesive film for circuit connections according to any one of claims 2 to 6, wherein the first thermosetting component includes a salt compound having a cation represented by the following formula (II) or the following formula (III) as the thermal cationic polymerization initiator. 【Transformation 3】 [In formula (II), R ５ and R ６ Each of these independently represents an organic group containing a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, or an aromatic hydrocarbon group having a substituent or being unsubstituted, and R ７ This represents an alkyl group having 1 to 6 carbon atoms. 【Chemistry 4】 [In formula (III), R ８ and R ９ each independently represents a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, or an organic group containing an aromatic hydrocarbon group which may have a substituent or is unsubstituted, R １０ and R １１ each independently represents an alkyl group having 1 to 6 carbon atoms.]

8. The average particle size of the aforementioned solder particles is 1 to 30 μm. A method for manufacturing an adhesive film for circuit connections according to any one of claims 1 to 7, wherein the C.V. value of the particle size of the solder particles is 20% or less.

9. A method for manufacturing an adhesive film for circuit connections according to any one of claims 1 to 8, wherein the solder particles include at least one selected from the group consisting of tin, tin alloys, indium, and indium alloys.

10. The method for manufacturing an adhesive film for circuit connections according to claim 9, wherein the solder particles include at least one selected from the group consisting of In-Bi alloy, In-Sn alloy, In-Sn-Ag alloy, Sn-Au alloy, Sn-Bi alloy, Sn-Bi-Ag alloy, Sn-Ag-Cu alloy, and Sn-Cu alloy.

11. A method for manufacturing an adhesive film for circuit connections according to any one of claims 1 to 10, wherein the solder particles have a flat portion on a part of their surface.

12. A method for manufacturing an adhesive film for circuit connections according to claim 11, wherein the ratio (B / A) of the diameter B of the planar portion to the diameter A of the solder particles satisfies the following formula. 0.01<B / A<1.0

13. A method for manufacturing an adhesive film for circuit connections according to any one of claims 1 to 12, wherein when a quadrilateral circumscribing the projection image of the solder particles is created by two pairs of parallel lines, and the distances between opposing sides are X and Y (where Y < X), X and Y satisfy the following formula. 0.8<Y / X≦1.0

14. A method for manufacturing an adhesive film for circuit connection according to any one of claims 1 to 13, wherein the plurality of recesses are formed in a predetermined pattern.

15. A circuit connection adhesive film containing solder particles, The device comprises a first adhesive layer containing a plurality of solder particles, a cured product of a photocurable component having radical curability, and a first thermosetting component that does not have radical curability, and a second adhesive layer provided on the first adhesive layer and containing a second thermosetting component. A circuit connection adhesive film in which at least a portion of the plurality of solder particles are arranged in a predetermined pattern in a plan view of the circuit connection adhesive film, and in a longitudinal cross-section of the circuit connection adhesive film, adjacent solder particles are arranged laterally with space between them.

16. A first circuit member having a first electrode, A second circuit member having a second electrode, A connection structure comprising a cured body of the adhesive film for circuit connection described in claim 15, and a connection portion that electrically connects the first electrode and the second electrode to each other via the solder and adheres the first circuit member and the second circuit member.

17. The circuit connection adhesive film according to claim 15 is placed between the surface on which the first electrode of the first circuit member having the first electrode is provided and the surface on which the second electrode of the second circuit member having the second electrode is provided. A method for manufacturing a connection structure, comprising: heating a laminate including the first circuit member, the circuit connection adhesive film, and the second circuit member while pressing the laminate in the thickness direction of the laminate, thereby electrically connecting the first electrode and the second electrode to each other via the solder and bonding the first circuit member and the second circuit member.

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