Circuit structure and manufacturing method thereof

Abstract

The present invention stabilizes electrical bonding between a metal layer of a deformable circuit board and a terminal pin. The circuit board includes a metal layer formed on one surface of a deformable insulating substrate, a reinforcing plate provided on the other surface of the insulating substrate opposite to the one surface thereof for suppressing bending deformation of the circuit board, a terminal pin inserted into a hole formed by penetrating the reinforcing plate and the insulating substrate from the side opposite to the metal layer and joined via a bonding material to a connection pad provided at one end of the metal layer, a fixing member for fixing the terminal pin within the hole, and a resin layer covering at least a portion of the one surface of the insulating substrate and the reinforcing plate.

Description

[Technical field]

[0001] The present invention relates to a circuit structure and a method for manufacturing the same. [Background technology]

[0002] A circuit structure is known in which a circuit board is provided, the circuit board comprising: an insulating plate having a plurality of holes formed therethrough in the thickness direction; and a circuit pattern formed on the insulating plate, the circuit pattern being made of conductive foil having an opening having an area smaller than that of at least one of the holes in the insulating plate, the opening being located at a position corresponding to the hole in the insulating plate. The circuit structure is provided with a single circuit board or a plurality of circuit boards stacked on top of each other so that the holes in the insulating plate correspond to each other. The circuit board is provided with through pins that are inserted into the holes in the insulating plate of the circuit board and into the opening in the conductive foil located at a position corresponding to at least one of the holes, and that bend the conductive foil toward the inner wall of the hole in the insulating plate and that come into contact with the bent conductive foil to electrically connect to the circuit board and to establish electrical continuity between predetermined areas of the circuit pattern of the circuit board (Patent Document 1).

[0003] A semiconductor device is also known which includes an insulated circuit board having a metal layer formed on one surface of an insulating substrate, a tubular connecting member joined to the metal layer via a bonding material, a terminal pin inserted into the connecting member, and a tubular reinforcing member arranged on the outer periphery of the connecting member, the reinforcing member being made of a material harder than the connecting member (Patent Document 2). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2010-27957 A [Patent Document 2] JP 2020-47377 A Summary of the Invention [Problem to be solved by the invention]

[0005] The present invention stabilizes the electrical connection between the metal layers of the deformable circuit board and the terminal pins. [Means for solving the problem]

[0006] In order to solve the above problem, the circuit structure according to claim 1 comprises: a circuit board having a metal layer formed on one surface of a deformable insulating substrate; Made of thermosetting resin material On the other surface of the insulating substrate opposite to the one surface A thickness greater than that of the insulating substrate Established Resin pressure from insert molding The circuit board Deflection A reinforcing plate for suppressing the From the opposite side of the metal layer, through the reinforcing plate and the insulating base material Same diameter The metal layer is then inserted into a hole formed in the hole and connected to a connection pad provided at one end of the metal layer via a bonding material. The anchor part A joined terminal pin; The adhesive strength of the adhesive to the terminal pin is higher than that of the inner wall of the hole, and the adhesive strength of the adhesive to the terminal pin is larger than that of the inner wall of the hole. Covering Forming a brim shape Resin pressure The terminal pin Movement of Constraints A fixing member for fixing the insert The above-mentioned formed by molding metal layer and the above Flange Shape Covering and protruding outward from the reinforcing plate A resin layer for fixing the terminal pin. It is characterized by:

[0007] The invention described in claim 2 is 1 In the circuit structure according to the present invention, The hole is larger than the terminal pin and smaller than the fillet of the bonding material. It is characterized by:

[0011] The invention as set forth in claim 3 is the circuit structure as set forth in claim 1 or 2, The fixing member includes a resin material which is any one or a combination of a thermosetting resin material, a two-component curable resin material, a photocurable resin material, and a moisture curable resin material, and is filled into the gap between the hole and the terminal pin and solidifies to fix the terminal pin in the hole. Constraints do, It is characterized by:

[0012] In order to solve the above problem, a method for producing a circuit structure according to claim 4 comprises the steps of: preparing a circuit board having a metal layer formed on one surface of a deformable insulating substrate; Made of thermosetting resin material On the other surface of the insulating substrate opposite to the one surface The thickness is thicker than that of the insulating base material, and the deflection of the circuit board caused by the resin pressure due to the insert molding is suppressed. forming a reinforcing plate; forming a hole through the reinforcing plate and the insulating base material; a step of inserting a terminal pin into the hole to electrically connect the terminal pin to a connection pad provided at one end of the metal layer; In the hole, a gap between the hole and the terminal pin is filled between the inner wall of the hole and the terminal pin. The adhesion to the terminal pin is stronger than to the inner wall of the hole. A resin material selected from a thermosetting resin material, a two-component curable resin material, a photocurable resin material, and a moisture curable resin material, or a combination thereof, is filled and solidified to form a hole larger than the hole and one surface of the reinforcing plate. Covering The terminal pin is attached by forming a flange shape. Constraints And a process of The above metal layer and the above Flange Shape of insert Covered with resin by molding protruding outward from the reinforcing plate and fixing the terminal pin. It is characterized by: Effect of the Invention

[0016] According to the invention described in claim 1, Regardless of the material of the reinforcing plate, the movement of the terminal pin is restricted within the hole. The electrical connection between the metal layer of the deformable circuit board and the terminal pin can be stabilized.

[0017] According to the invention as recited in claim 2, the fixing member can be held within the hole.

[0021] Claim 3 According to the invention described in the above, the gap between the hole and the terminal pin can be easily filled with the fixing member, thereby restricting the movement of the terminal pin within the hole.

[0022] Claim 4 According to the invention described in The gap between the hole and the terminal pin can be easily filled with a fixing material to restrict the movement of the terminal pin within the hole. The electrical connection between the metal layer of the deformable circuit board and the terminal pin can be stabilized. [Brief description of the drawings]

[0026] [Figure 1] FIG. 1A is a schematic plan view showing an example of a circuit structure according to this embodiment, and FIG. 1B is a schematic cross-sectional view. [Diagram 2] FIG. 2A is a schematic plan view showing the circuit board according to this embodiment, and FIG. 2B is a schematic cross-sectional view showing a reinforcing plate provided on the circuit board. [Diagram 3] 11A and 11B are diagrams illustrating the inclination of a terminal pin. [Figure 4] 11A and 11B are diagrams illustrating the fixing of a terminal pin by a fixing member. [Diagram 5] FIG. 13 is a diagram illustrating the fixing of a terminal pin by a fixing member according to a modified example. [Figure 6] FIG. 6A is a schematic diagram for explaining the bending of a circuit board due to the resin pressure of molten resin, and FIG. 6B is a schematic diagram for explaining the inclination of a terminal pin due to the resin pressure of molten resin. [Figure 7] FIG. 1 is a flow chart showing an example of a schematic procedure of a method for manufacturing a circuit structure. [Figure 8] 1A to 1C are partial schematic cross-sectional views of a circuit structure for illustrating a manufacturing process of the circuit structure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0027] Next, specific examples of the embodiments of the present invention will be described with reference to the drawings, but the present invention is not limited to the following embodiments. In the following explanation using the drawings, it should be noted that the drawings are schematic and the ratios of the dimensions, etc. may differ from the actual ones, and in order to facilitate understanding, illustrations other than those of components necessary for the explanation have been omitted as appropriate.

[0028] (1) Overall configuration of the circuit structure FIG. 1A is a schematic plan view showing an example of a circuit structure 1 according to this embodiment, FIG. 1B is a schematic cross-sectional view, FIG. 2A is a schematic plan view showing a circuit board according to this embodiment, FIG. 2B is a schematic cross-sectional view showing a reinforcing plate provided on the circuit board, and FIG. 3 is a diagram explaining the inclination of a terminal pin. The configuration of a circuit structure 1 according to this embodiment will be described below with reference to the drawings.

[0029] In FIG. 1A, the mounting components P and the resin layer 9 are indicated by dashed lines, and the bonding material 6 is not shown. As shown in FIG. 1, the circuit structure 1 is configured to include a circuit board 4 (see FIG. 2A) having a metal layer 3 formed on one surface 2a of an insulating base material 2, a reinforcing plate 5 provided on the other surface 2b opposite to the one surface 2a of the insulating base material 2 and suppressing bending deformation of the circuit board 4, a terminal pin 7 inserted into a hole 11 formed by penetrating the reinforcing plate 5 and the insulating base material 2 from the side opposite the metal layer 3 and joined to the metal layer 3 via solder as an example of a bonding material 6, a fixing member 8 that fixes the terminal pin 7 within the hole 11, and a resin layer 9 that covers at least a portion of the circuit board 4 and the reinforcing plate 5. In the circuit structure 1, the fixing member 8 restrains the movement of the terminal pin 7 within the hole 11, thereby stabilizing the electrical connection between the metal layer 3 of the deformable circuit board 4 and the terminal pin 7.

[0030] (insulating substrate) In this embodiment, the insulating substrate 2 is a deformable insulating film- or plate-shaped substrate made of a synthetic resin material. Here, the "deformable substrate" means a substrate that can be deformed after the metal layer 3 is disposed thereon, that is, a substrate that can be deformed from a substantially flat two-dimensional shape to a substantially solid three-dimensional shape by thermoforming, vacuum forming, pressure forming, or the like.

[0031] Examples of the insulating substrate 2 include insulating films made of thermoplastic resin materials such as polyesters such as polyethylene terephthalate (PET) and polyethylene naphthalate (PEN), polyamides (PA) such as nylon 6-10 and nylon 46, polyether ether ketone (PEEK), acryl butadiene styrene (ABS), polymethyl methacrylate (PMMA), and polyvinyl chloride (PVC), insulating films made of thermosetting resin materials such as phenol, epoxy, polyimide (PI), unsaturated polyester, polyurethane, silicone, and oxetane, and insulating plates such as glass epoxy (FR-4) and glass composite (CEM3).

[0032] The thickness of the insulating base material 2 is not particularly limited, but is preferably 5 μm to 3 mm, more preferably 12 μm to 1 mm, and most preferably 50 μm to 200 μm. If the insulating base material 2 is too thin, the strength may be insufficient and the insulating base material 2 may be significantly distorted during the plating process of the metal layer 3. Note that this thickness is a condition when the insulating base material 2 is a film-like base material, and the insulating base material 2 to which the present invention is applied is not limited to a film-like base material.

[0033] In order to uniformly apply the conductive ink containing metal nanoparticles to the surface of the insulating substrate 2, it is preferable to perform a surface treatment. Examples of the surface treatment that can be used include a corona treatment, a plasma treatment, a solvent treatment, and a primer treatment.

[0034] Furthermore, the insulating base material 2 has a hole 21 (see FIG. 2B ) that becomes part of the hole portion 11. The hole 21 is formed so as to penetrate in the thickness direction, and a terminal pin 7 (described later) is inserted through the hole 21 to electrically connect the terminal pin 7 to a connection pad 3A formed at one end of a metal layer 3 arranged on one surface 2a of the insulating base material 2.

[0035] (metal layer) When disposing the metal layer 3 on one surface 2a of the insulating substrate 2, a base layer (not shown) made of a catalyst such as metal nanoparticles that triggers the growth of metal plating is first formed in a predetermined pattern. The base layer is formed by applying a catalyst ink such as metal nanoparticles onto the insulating substrate 2, followed by drying and baking.

[0036] The thickness (μm) of the underlayer is preferably 0.1 to 20 μm, more preferably 0.2 to 5 μm, and most preferably 0.5 to 2 μm. If the underlayer is too thin, the strength of the underlayer may be reduced. If the underlayer is too thick, the manufacturing cost may increase because metal nanoparticles are more expensive than normal metals.

[0037] Examples of the catalyst material include gold, silver, copper, palladium, and nickel. From the viewpoint of electrical conductivity, gold, silver, and copper are preferred, and copper, which is cheaper than gold and silver, is most preferred.

[0038] The particle size (nm) of the catalyst is preferably 1 to 500 nm, more preferably 10 to 100 nm. If the particle size is too small, the reactivity of the particles may increase, which may adversely affect the storage stability of the ink. If the particle size is too large, it may be difficult to form a uniform thin film, and the ink particles may be more likely to settle.

[0039] The metal layer 3 is formed on the underlayer by electrolytic plating or electroless plating. As the plating metal, copper, nickel, tin, silver, gold, etc. can be used, but copper is most preferably used from the viewpoints of extensibility, conductivity, and cost.

[0040] The thickness of the plating layer is preferably 0.03 to 100 μm, more preferably 1 to 35 μm, and most preferably 3 to 18 μm. If the plating layer is too thin, the mechanical strength may be insufficient and the electrical conductivity may not be sufficient for practical use. If the plating layer is too thick, the time required for plating may be long, and the manufacturing cost may increase.

[0041] A plurality of connection pads 3A are provided at one end of the metal layer 3. Holes 3Aa (see FIG. 2B ) communicating with the holes 11 are formed in the connection pads 3A, and a plurality of terminal pins 7 for electrically connecting to an external device provided outside the circuit structure 1 are electrically joined by a bonding material 6.

[0042] (Mounting parts) A plurality of mounting components P may be attached to the metal layer 3 via connection pads 3B (see FIG. 2A ). The mounting components P may include control circuits, contact sensing and light detection components such as strain, resistance, capacitance, TIR, tactile or vibration components such as piezoelectric actuators or vibration motors, light emitting components such as LEDs, sound generating or receiving components such as microphones and speakers, device operating components such as memory chips, programmable logic chips and CPUs, digital signal processors (DSPs), ALS devices, PS devices, processing devices, MEMS, etc.

[0043] (Reinforcing plate) A reinforcing plate 5 for suppressing bending deformation of the circuit board 4 is provided on the other surface 2b of the insulating base material 2 opposite to the one surface 2a. As shown in FIG. 2, the reinforcing plate 5 has a through hole 51 formed in accordance with the hole 21 formed in the insulating base material 2, and is fixed by adhesion so as to be in close contact with the other surface 2b of the insulating base material 2. Examples of the adhesion method include fixing with an adhesive or attaching with a double-sided tape so that the reinforcing plate 5 does not shift due to the resin pressure of the molten resin when the circuit board 4 is covered with the resin layer 9. Note that the through hole 51 is formed by forming a through hole penetrating the reinforcing plate 5 and the insulating base material 2 in the thickness direction as the hole portion 11 while the reinforcing plate 5 is adhesively fixed to the circuit board 4, as described later. The material of the reinforcing plate 5 is not particularly limited, but from the viewpoint of strength, it is preferable that the reinforcing plate 5 be made of a thermosetting resin material such as glass epoxy (FR-4).

[0044] The through hole 51 communicates with the hole 21 formed in the insulating base material 2, and is formed to be larger than the terminal pin 7 and smaller than the fillet 6a of the bonding material 6 that electrically bonds the terminal pin 7 to the connection pad 3A. As a result, the movement of the terminal pin 7 inside the through hole 51 can be restricted by filling and solidifying the fixing member 8 between the terminal pin 7 inserted into the through hole 51 and the inner wall 51a of the through hole 51.

[0045] 3, when the terminal pin 7 is positioned offset to one side with respect to the through hole 51, the angle at which the terminal pin 7 is tilted due to the resin pressure of the molten resin when the resin layer 9 is insert-molded changes depending on the plate thickness of the reinforcing plate 5 and the hole diameter of the through hole 51. In this embodiment, the plate thickness of the reinforcing plate 5 is preferably at least 0.5 mm or more, and more preferably 1 mm or more.

[0046] (Fixing member) FIG. 4 is a diagram illustrating the fixing of the terminal pin 7 by the fixing member 8. As shown in FIG. As shown in FIG. 4, the fixing member 8 is embedded between the inner wall 51a of the through hole 51 and the terminal pin 7 so as to fill the gap between the through hole 51 and the terminal pin 7. Examples of materials for the fixing member 8 include a thermosetting resin material, a two-component curable resin material, a photocurable resin material, and a moisture curable resin material, or a combination of these curable resin materials. Specifically, various resins such as epoxy resin, urethane resin, acrylic resin, polyimide resin, polyamide resin, bismaleimide resin, phenol resin, polyester resin, silicone resin, and oxetane resin can be used. These may be used alone or in combination of two or more kinds.

[0047] Among these curable resin materials, moisture-curable resin materials containing cyanoacrylate have low viscosity in the monomer state before curing, and are easily filled deep into the space between the inner wall 51a of the through hole 51 and the terminal pin 7, and after filling, they solidify in a short time to fix the terminal pin 7 within the through hole 51.

[0048] "Variation 1" FIG. 5A is a diagram showing the fixing of terminal pin 7 by fixing member 8A according to Modification 1. FIG. The fixing member 8A has a stronger adhesive strength to the terminal pin 7 than to the inner wall 51a of the through hole 51, and forms a flange shape 81 larger than the through hole 51 between the through hole 51 and the terminal pin 7 when solidified. As a result, as shown diagrammatically in FIG. 5A, a brim shape 81 larger than through hole 51 is formed at the entrance of through hole 51, so that the movement of terminal pin 7 can be restricted even if the material of reinforcing plate 5 is a poorly adhesive material such as a fluorine-based resin.

[0049] "Variation 2" FIG. 5B is a diagram showing the fixing of the terminal pin 7 by a fixing member 8B according to the second modification. 5, the fixing member 8B has a stronger adhesive strength to the terminal pin 7 than to the inner wall 51a of the through hole 51, and when solidified, forms a fillet shape 82 larger than the through hole 51 between the through hole 51 and the terminal pin 7. Epoxy resin is particularly suitable as a material for such fixing member 8B. As a result, as shown typically in FIG. 5B, a fillet shape 82 larger than the through hole 51 is formed at the entrance of the through hole 51, making it possible to restrict the movement of the terminal pin 7.

[0050] (Resin layer) FIG. 6A is a schematic diagram for explaining the bending of circuit board 4 due to the resin pressure of molten resin, and FIG. 6B is a schematic diagram for explaining the inclination of terminal pin 7 due to the resin pressure of molten resin. The resin layer 9 is formed so as to cover at least a part of the circuit board 4 and the reinforcing plate 5. As will be described later, the resin layer 9 is formed by insert molding a molten resin in a state in which the circuit board 4, having the terminal pins 7 joined to the connection pads 3A of the metal layer 3, is positioned and set in an injection molding die K (see FIG. 8E).

[0051] At this time, the injected molten resin exerts a resin pressure on the circuit board 4 to warp the circuit board 4 as shown in Fig. 6A, and also exerts a resin pressure on the terminal pin 7 to tilt the terminal pin 7 as shown in Fig. 6B. This causes the bond between the connection pad 3A and the terminal pin 7 to deform, causing the fillet 6a of the bonding material 6 to rise up from the metal layer 3 together with the connection pad 3A, which may cause the electrical connection to become unstable.

[0052] According to this embodiment, the fixing member 8 is embedded between the terminal pin 7 and the inner wall 51a of the through hole 51 so as to fill the gap between the terminal pin 7 and the through hole 51 of the reinforcing plate 5 through which the terminal pin 7 is inserted, and fixes the terminal pin 7 inside the through hole 51. This restrains the movement of the terminal pin 7 when the resin layer 9 is insert-molded, stabilizing the electrical connection.

[0053] The resin layer 9 is a thermoplastic resin made of an injection moldable thermoplastic resin material. Specifically, a thermoplastic resin containing polycarbonate (PC), polyethylene terephthalate (PET), polymethyl methacrylate (PMMA), polyamide (PA), acryl butadiene styrene (ABS), polyethylene (PE), polypropylene (PP), modified polyphenylene ether (m-PPE), modified polyphenylene oxide (m-PPO), cycloolefin copolymer (COC), cycloolefin polymer (COP), polytetrafluoroethylene (PTFE), polyvinyl chloride (PVC), or a mixture thereof can be used.

[0054] (2) Method for manufacturing a circuit structure FIG. 7 is a flow chart showing an example of the outline of the steps of a method for producing the circuit structure 1, and FIG. 8 is a partial schematic cross-sectional view of the circuit structure 1 for illustrating the manufacturing process of the circuit structure 1.

[0055] As shown in FIG. 7 , the circuit structure 1 is manufactured through the following steps: a circuit board preparation process S11 for preparing a circuit board 4 having a metal layer 3 formed on one surface 2a of an insulating base material 2; a reinforcing plate formation process S12 for forming a reinforcing plate 5 on the other surface 2b opposite to the one surface 2a of the insulating base material 2; a hole formation process S13 for forming a hole 11 by penetrating the reinforcing plate 5 and the insulating base material 2; a joining process S14 for inserting a terminal pin 7 into the hole 11 to electrically join the terminal pin 7 and a connection pad 3A provided on one end of the metal layer 3; a fixing process S15 for fixing the terminal pin 7 in the hole 11; and a resin filling process S16 for insert-molding a resin layer 9 into the circuit board 4.

[0056] (Circuit board preparation process S11) In the circuit board preparation step S11, first, in order to arrange the metal layer 3 on the insulating base material 2 that is a substantially flat film formed in a predetermined shape and size, a base layer made of catalyst particles such as metal nanoparticles that trigger metal plating growth is formed in a predetermined pattern on the insulating base material 2. Note that, in order to uniformly apply the catalyst ink made of catalyst particles such as metal nanoparticles to the insulating base material 2, it is preferable to perform a surface treatment such as a corona treatment, a plasma treatment, a solvent treatment, a primer treatment, etc.

[0057] Methods for applying a catalyst ink consisting of catalyst particles such as metal nanoparticles onto the insulating substrate 2 include inkjet printing, silk screen printing, gravure printing, offset printing, flexographic printing, roller coater, brush coating, spraying, knife jet coater, pad printing, gravure offset printing, die coater, bar coater, spin coater, comma coater, impregnation coater, dispenser and metal mask methods, but in this embodiment, inkjet printing is used.

[0058] The underlayer formed on the insulating base material 2 is subjected to electrolytic plating or electroless plating to deposit a plating metal on the surface and inside of the underlayer, forming the metal layer 3. The plating method is the same as that using a known plating solution and plating process, and specific examples include electroless copper plating and electrolytic copper plating. In addition, a plurality of connection pads 3A are formed on one end of the metal layer 3.

[0059] (Reinforcing plate forming process S12) After the circuit board preparation step S11, a reinforcing plate 5 is attached by adhesion to the other surface 2b opposite to the one surface 2a of the insulating base material 2 (see FIG. 8A).

[0060] (Hole formation step S13) In the circuit board 4 to which the reinforcing plate 5 is attached, a hole 11 is formed penetrating in the thickness direction of the reinforcing plate 5 and the insulating base material 2 (see FIG. 8B). The hole 11 is a through hole through which the terminal pin 7 is inserted, and is formed to be larger than the terminal pin 7 and smaller than the fillet 6a of the bonding material 6 that electrically bonds the terminal pin 7 to the connection pad 3A.

[0061] (Joining process S14) After solder paste is applied onto the connection pad 3A of the metal layer 3 using a dispenser device or the like, the terminal pin 7 is inserted into the hole 11 formed in the through hole formation process S13, and the solder, which is an example of a bonding material 6, is melted and solidified to bond the anchor portion of the terminal pin 7 onto the connection pad 3A via the solder 6 (see Figure 8C).

[0062] (Fixed process S15) In the fixing step S15, the solder portion of the circuit board 4 that has been subjected to the joining step S14, particularly the rear side of the connection pad 3A, is cleaned to remove the flux, and then a fixing member 8 is filled between the inner wall 51a of the through hole 51 formed in the reinforcing plate 5 and the terminal pin 7 so as to fill the gap between the hole portion 11 and the terminal pin 7. The filling fixing member 8 is made of a moisture-curing resin material containing cyanoacrylate, and when solidified, forms a flange shape 81 larger than the through hole 51 between the through hole 51 and the terminal pin 7 at the entrance of the through hole 51 (see FIG. 8D). Alternatively, the fixing member 8 may be made of epoxy resin, which forms a fillet shape between the through hole 51 and the terminal pin 7 to restrain the movement of the terminal pin 7.

[0063] (Resin filling process S16) In the resin filling step S16, the circuit board 4 with the terminal pins 7 fixed by the fixing members 8 is positioned and set in the injection molding die K (see FIG. 8E), and the injection molding die K is closed to fill the cavity CA with molten resin. The resin filled in the cavity CA forms a resin layer 9 so as to cover the circuit board 4 and the reinforcing plate 5 (see FIG. 8F).

[0064] As described above, according to the method for manufacturing the circuit structure 1 of the present embodiment, the fixing member 8 is filled between the inner wall 51a of the through hole 51 and the terminal pin 7 so as to fill the gap between the through hole 51 of the reinforcing plate 5 through which the terminal pin 7 is inserted and the terminal pin 7, and then solidifies, thereby fixing the terminal pin 7 in the through hole 51. This restrains the movement of the terminal pin 7 when the resin layer 9 is insert-molded, stabilizing the electrical connection.

[0065] In this embodiment, the circuit structure 1 configured with the resin layer 9 covering at least a part of the circuit board 4 and the reinforcing plate 5 has been described, but even in the circuit structure 1 not having the resin layer 9, there is a risk that the electrical connection between the connection pad 3A and the terminal pin 7 may become unstable when an external load acts on the circuit board 4 or a horizontal load acts on the terminal pin 7. Therefore, even in the circuit structure 1 not having the resin layer 9, by embedding a fixing member 8 between the inner wall 51a of the through hole 51 in the reinforcing plate 5 and the terminal pin 7 so as to fill the gap between the through hole 51 and the terminal pin 7, it is possible to restrain the movement of the terminal pin 7 and stabilize the electrical connection. [Explanation of symbols]

[0066] 1...Circuit structure 2. Insulating substrate 2a...One side (metal layer side), 2b...Other side, 21...hole 3···metal layer, 3A···connection pad 4. Circuit board 5. Reinforcement plate 6...Joining material 7 Terminal pin 8... Fixing member, 81... flange shape, 82... fillet shape K...Injection mold CA···Cavity

Claims

1. a circuit board having a metal layer formed on one surface of a deformable insulating substrate; a reinforcing plate provided on the other surface of the insulating base material opposite to the one surface and configured to suppress bending deformation of the circuit board; a terminal pin that is inserted into a hole formed by penetrating the reinforcing plate and the insulating base from the side opposite to the metal layer and that is joined via a bonding material to a connection pad provided at one end of the metal layer; a fixing member that has a stronger adhesive force to the terminal pin than an inner wall of the hole and that solidifies to form a flange shape larger than the hole to fix the terminal pin; A resin layer covering at least a portion of the circuit board and the reinforcing plate, A circuit structure comprising:

2. The hole is larger than the terminal pin and smaller than the fillet of the bonding material.

2. The circuit structure according to claim 1.

3. The fixing member includes a curable resin material which is any one or a combination of a thermosetting resin material, a two-component curable resin material, a photocurable resin material, and a moisture curable resin material, and fixes the terminal pin in the hole by filling the gap between the hole and the terminal pin and solidifying.

3. The circuit structure according to claim 1 or 2.

4. preparing a circuit board having a metal layer formed on one surface of a deformable insulating substrate; forming a reinforcing plate on another surface of the insulating base material opposite to the one surface; forming a hole through the reinforcing plate and the insulating base material; a step of inserting a terminal pin into the hole to electrically connect the terminal pin to a connection pad provided at one end of the metal layer; a step of filling a resin material, which is any one or a combination of a thermosetting resin material, a two-component curable resin material, a photocurable resin material, and a moisture curable resin material, between an inner wall of the hole and the terminal pin so as to fill a gap between the hole and the terminal pin in the hole, and solidifying the resin material to form a flange shape larger than the hole, thereby fixing the terminal pin; and covering the one surface and at least a portion of the reinforcing plate with resin. A method for manufacturing a circuit structure comprising the steps of:

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