JP6903300B1 - Electronic device and its manufacturing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electronic device and a manufacturing method capable of electrically joining external connection terminals with high position accuracy on a metal wiring pattern formed on a thermoformed base material while reducing the number of parts. SOLUTION: A base material made of a synthetic resin material and capable of being deformed from a substantially flat two-dimensional shape to a substantially three-dimensional shape, a metal wiring pattern arranged on the base material, and heat molding on the base material. An external connection terminal for electrically connecting an external element provided outside the base material by contacting the metal wiring pattern with a recess formed in a three-dimensional shape in the thickness direction of the base material, and an external surface. A housing that surrounds the external connection terminal is formed so that the terminal surface, which is the surface of the connection terminal, is exposed, and a resin layer that covers at least one surface of the base material and a joint that electrically joins the metal wiring pattern and the external connection terminal at a recess. A means and a coating layer filled in the recesses to cover the joining means were provided. [Selection diagram] Fig. 3

Description

The present invention relates to an electronic device and a method for manufacturing the same.

An electronic circuit that performs a predetermined process, a substrate on which the electronic circuit is arranged, and a pad provided on the substrate by bending one end thereof are joined and electrically connected to the electronic circuit via the pad. Also, the pin header used for positioning in the secondary molding with the other end serving as the connector terminal and one end of the electronic circuit, substrate and pin header are resin-sealed so that the connector terminal is exposed. A module including the above-mentioned primary molded body is known (Patent Document 1).

Receives light emitted by a light guide plate, an electrode forming surface having a pair of positive and negative element electrodes, a light emitting element having a mounting surface opposite to the electrode forming surface, a conductive wire connected to the element electrode, and light emitted by the light emitting element. This is a method for manufacturing a light emitting module including a wavelength conversion member that converts light into light having a different wavelength, and a sealing resin that seals the light emitting element and the wavelength conversion member. The step of preparing a light guide plate and the light guide plate. A step of arranging the wavelength conversion member on the top, a step of mounting the light emitting element on the wavelength conversion member with the electrode forming surface facing up and the mounting surface facing down, and the light guide plate. A step of forming a light-reflecting layer around the light-emitting element, a step of forming an electrode layer on the upper surface of the light-reflecting layer, a step of connecting the electrode layer and the element electrode with a wire, and an electrode. A method for manufacturing a light emitting module including a step of sealing a layer, a light reflecting layer, and a light emitting element with a sealing resin is also known (Patent Document 2).

JP-A-2017-207318 JP-A-2019-175892

The present invention provides an electronic device and a manufacturing method capable of reducing the number of parts and electrically joining external connection terminals on a metal wiring pattern formed on a thermoformed base material with high position accuracy.

In order to solve the above problems, the electronic device according to claim 1 is used.
A base material made of synthetic resin material that can be transformed from a substantially flat two-dimensional shape to a substantially three-dimensional shape,
The metal wiring pattern arranged on the base material and
The base material is thermoformed to come into contact with the metal wiring pattern at a recess shaped into the three-dimensional shape in the thickness direction of the base material, and an external element provided outside the base material is electrically connected. With an external connection terminal for connecting to
A housing that surrounds the external connection terminal is formed so that the terminal surface, which is the surface of the external connection terminal, is exposed, and a resin layer that covers at least one surface of the base material is formed.
A joining means for electrically joining the metal wiring pattern and the external connection terminal in the recess,
The recess is filled with the metal wiring pattern and a coating layer that integrally covers the external connection terminal and the joining means.
It is characterized by that.

The invention according to claim 2 is the electronic device according to claim 1.
The resin layer is formed on one surface of the base material via a toned adhesive layer that makes the metal wiring pattern invisible from the outside.
It is characterized by that.

The invention according to claim 3 is the electronic device according to claim 1 or 2.
The resin layer is formed of a transparent resin material on the other surface opposite to one surface of the base material via a translucent adhesive layer.
It is characterized by that.

In order to solve the above problems, the method for manufacturing an electronic device according to claim 4 is as follows.
A base material made of synthetic resin material that can be transformed from a substantially flat two-dimensional shape to a substantially three-dimensional shape,
The metal wiring pattern arranged on the base material and
The base material is thermoformed to come into contact with the metal wiring pattern at a recess shaped into the three-dimensional shape in the thickness direction of the base material, and an external element provided outside the base material is electrically connected. With an external connection terminal for connecting to
A housing that surrounds the external connection terminal is formed so that the terminal surface, which is the surface of the external connection terminal, is exposed, and a resin layer that covers at least one surface of the base material is formed.
A joining means for electrically joining the metal wiring pattern and the external connection terminal in the recess,
A method of manufacturing an electronic device including a coating layer that fills the recess and covers the joining means.
The process of preparing the base material and
The step of arranging the metal wiring pattern on the base material and
A step of positioning and placing the base material on which the metal wiring pattern is arranged and the external connection terminal on a mold to shape the recess and at the same time injection molding the resin layer.
A process of electrically joining the metal wiring pattern and the external connection terminal by a joining means,
A coating step of filling the recess with the coating layer and integrally covering the metal wiring pattern, the external connection terminal, and the joining means is executed in order.
It is characterized by that.

In order to solve the above problems, the method for manufacturing an electronic device according to claim 5 is as follows.
A base material made of synthetic resin material that can be transformed from a substantially flat two-dimensional shape to a substantially three-dimensional shape,
The metal wiring pattern arranged on the base material and
The base material is thermoformed to come into contact with the metal wiring pattern at a recess shaped into the three-dimensional shape in the thickness direction of the base material, and an external element provided outside the base material is electrically connected. With an external connection terminal for connecting to
A housing that surrounds the external connection terminal is formed so that the terminal surface, which is the surface of the external connection terminal, is exposed, and a resin layer that covers at least one surface of the base material is formed.
A joining means for electrically joining the metal wiring pattern and the external connection terminal in the recess,
A method of manufacturing an electronic device including a coating layer that fills the recess and covers the joining means.
The process of preparing the base material and
The step of arranging the metal wiring pattern on the base material and
The base material on which the metal wiring pattern is arranged is positioned and placed on a mold to form the recess, and at the same time, the base material is covered on the other surface opposite to the one on which the metal wiring pattern is arranged. The process of injection molding the resin layer and
A process of electrically joining the metal wiring pattern and the external connection terminal by a joining means,
A coating step of filling the recess with the coating layer to integrally cover the metal wiring pattern, the external connection terminal, and the joining means.
The steps of injection molding the resin layer so as to cover one surface on which the metal wiring pattern is arranged are executed in order.
It is characterized by that.

According to the first aspect of the present invention, the number of parts can be reduced and the external connection terminals can be electrically joined on the metal wiring pattern formed on the thermoformed base material with high position accuracy.

According to the second aspect of the present invention, the metal wiring pattern can be made invisible to maintain the aesthetic appearance.

According to the invention of claim 3, when the decoration is applied to the inside, the decoration can be made visible while being protected.

According to the invention of claim 4, the recess for arranging the coating layer is formed integrally with the resin layer, and the external connection terminal is positioned accurately on the metal wiring pattern formed on the thermoforming base material. Can be placed and electrically joined.

According to the invention of claim 5, a recess for arranging the coating layer and an insertion hole for inserting the external connection terminal are formed integrally with the resin layer, and a metal wiring pattern formed on a thermoforming base material. External connection terminals can be arranged on top with high positional accuracy and electrically joined.

It is a plan schematic diagram which shows an example of the electronic device which concerns on this embodiment (the resin layer is not shown). It is a partial cross-sectional schematic diagram which shows an example of the electronic device which concerns on this embodiment. It is a partial cross-sectional schematic diagram which shows an example of another aspect of the electronic device which concerns on this embodiment. It is a flowchart which shows an example of the schematic procedure of the manufacturing method of the electronic device which concerns on this embodiment. It is a partial cross-sectional schematic diagram of the electronic device for demonstrating the manufacturing process of the electronic device which concerns on this embodiment. It is a partial cross-sectional schematic diagram of the electronic device for demonstrating another manufacturing process of the electronic device which concerns on this embodiment. It is a partial cross-sectional schematic diagram of the electronic device for demonstrating another manufacturing process of the electronic device which concerns on this embodiment. It is a partial cross-sectional schematic diagram which shows the other aspect of the electronic device which concerns on this embodiment.

Next, a specific example of the embodiment 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 explanation using the following drawings, it should be noted that the drawings are schematic and the ratio of each dimension is different from the actual one, which is necessary for the explanation for easy understanding. Illustrations other than the members are omitted as appropriate.

(1) Overall Configuration of Electronic Device FIG. 1 is a schematic plan view showing an example of the electronic device 1 according to the present embodiment with the resin layer not shown, and FIG. 2 is a portion showing an example of the electronic device 1 according to the present embodiment. The schematic cross-sectional view and FIG. 3 are partial cross-sectional schematic views showing an example of another aspect of the electronic device 1 according to the present embodiment.
Hereinafter, the configuration of the electronic device 1 according to the present embodiment will be described with reference to the drawings.

As shown in FIGS. 1 and 2, the electronic device 1 includes a deformable insulating base material 2 made of a synthetic resin material, a metal wiring pattern 3 arranged on the base material 2, and a metal wiring pattern 3. The external connection terminal 4 joined by the joining means, the joining member 5 for joining the metal wiring pattern 3 and the external connection terminal 4, the resin layer 6 covering at least one surface of the base material 2, and the coating covering the joining member 5. It is configured to include a layer 7.

(Base material)
The insulating and deformable base material 2 used in the present embodiment is not particularly limited to a film-like base material, but will be described below as a film-like base material. Here, the "deformable base material" can be deformed after the metal wiring pattern 3 is placed, that is, formed from a substantially flat two-dimensional shape to a substantially three-dimensional shape by thermoforming, vacuum forming, or compressed air forming. Means a substrate that can be made.
The material of the base material 2 is an insulating and deformable thermoplastic resin, and when the melting point Tm is present, the temperature is preferably 150 ° C. or higher, more preferably 200 ° C. or higher.
The range of the glass transition point Tg of the base material 2 is preferably 20 ° C. to 250 ° C., more preferably 50 ° C. to 200 ° C., and most preferably 70 ° C. to 150 ° C. If the glass transition point Tg is too low, the distortion of the base material 2 may increase when the metal wiring pattern 3 is formed.

The material of the base material 2 is not particularly limited as long as it meets the conditions of the melting point Tm and the glass transition point Tg as described above, but specifically, polyesters such as polyethylene terephthalate (PET) and polyethylene naphthalate (PEN) are used. Examples thereof include polyamides such as nylon 6-10 and nylon 46, and thermoplastic resins such as polyetheretherketone (PEEK), ABS, PMMA, and polyvinyl chloride.
In particular, polyester is more preferable, and among them, polyethylene terephthalate (PET) is most preferable because it has a good balance of economy, electrical insulation, chemical resistance and the like.

The thickness of the base material 2 is preferably 5 μm to 3 mm, more preferably 12 μm to 1 mm, and most preferably 50 μm to 200 μm. If the thickness of the base material 2 is too thin, the strength may be insufficient and the distortion of the base material 2 may increase during the plating process of the metal wiring pattern 3. This thickness is a condition when the 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 the film-like base material.

The surface of the base material 2 is preferably surface-treated in order to uniformly apply the catalyst ink such as metal nanoparticles. As the surface treatment, for example, corona treatment, plasma treatment, solvent treatment, and primer treatment can be used.

The film-like base material 2 made of such a deformable thermoplastic resin is shaped from a substantially flat two-dimensional shape to a substantially three-dimensional shape according to the required usage mode of the electronic device 1. ..

(Metal wiring pattern)
When the metal wiring pattern 3 is arranged on the surface of the base material 2, the base layer 3a made of a catalyst such as metal nanoparticles that triggers the growth of metal plating is formed in a predetermined pattern.
The base layer 3a is formed by applying a catalyst ink such as metal nanoparticles on the base material 2 and then drying and firing the base layer 3a.

The thickness of the base layer 3a is preferably 100 nm to 20 μm, more preferably 200 nm to 5 μm, and most preferably 500 nm to 2 μm. If the base layer 3a is too thin, the strength of the base layer 3a may decrease. Further, if the base layer 3a is too thick, the metal nanoparticles are more expensive than ordinary metals, which may increase the manufacturing cost.

As the material of the catalyst, gold, silver, copper, palladium, nickel and the like are used, and gold, silver and copper are preferable from the viewpoint of conductivity, and copper, which is cheaper than gold and silver, is most preferable.

The particle size of the catalyst is preferably 1 nm to 500 nm, more preferably 10 nm to 100 nm. If the particle size is too small, the reactivity of the particles becomes high, which may adversely affect the storage stability and stability of the ink. If the particle size is too large, it becomes difficult to form a thin film uniformly, and there is a risk that ink particles are likely to precipitate.

The metal wiring pattern 3 is formed on the base layer 3a by electrolytic plating or electroless plating. As the plating metal, copper, nickel, tin, silver, gold and the like can be used, but copper is most preferable from the viewpoint of extensibility, conductivity and price.

The thickness of the plating layer is preferably 0.03 μm to 100 μm, more preferably 1 μm to 35 μm, and most preferably 3 μm to 18 μm. If the plating layer is too thin, the mechanical strength may be insufficient and the conductivity may not be sufficiently obtained in practice. If the plating layer is too thick, the time required for plating becomes long, which may increase the manufacturing cost.

Although the metal wiring pattern 3 shows an example in which the touch sensor 3A is arranged in FIG. 1, a plurality of electronic components may be attached to the metal wiring pattern 3. Electronic components include control circuits, distortion, resistance, capacitance, contact sensing such as TIR, and light detection components, tactile or vibrating components such as piezoelectric actuators or vibration motors, light emitting components such as LEDs, microphones and speakers. Such as sounding or receiving sound, a memory chip, a programmable logic chip, a device operating component such as a CPU, a digital signal processor (DSP), an ALS device, a PS device, a processing device, a MEMS, and the like.

(External connection terminal)
As shown in FIG. 2, an external connection terminal 4 for electrically connecting to an external element provided outside the electronic device 1 is joined to the metal wiring pattern 3.
The external connection terminal 4 is formed in a quadrangular prism shape using, for example, a copper alloy or the like. As an example, the surface of the external connection terminal 4 may be nickel-plated, and the nickel plating may be plated with a metal such as gold or tin or an alloy containing these metals. The pitch of the external connection terminal 4 corresponds to the standard of the connector to which the connection is made. The external connection terminal 4 is composed of, for example, a terminal portion 4a serving as a connector terminal, an anchor portion 4b joined by a metal wiring pattern 3 and a joining member 5, and the anchor portion 4b is joined to the metal wiring pattern 3 by the joining member 5. Will be done.

(Joining member)
As shown in FIG. 2A, the anchor portion 4b of the external connection terminal 4 is joined to the metal wiring pattern 3 by a joining member 5 as an example of the joining means. Examples of the joining member 5 include solder 5A. The solder 5A is preferably a low-temperature solder having a melting temperature lower than the softening point of the base material 2, for example, an alloy (SnBi) of tin (Sn) and bismuth (Bi), tin (Sn) and bismuth (Bi). Alloy of nickel (Ni) and copper (Cu) (SnBiNiCu), alloy of tin (Sn) and bismuth (Bi) and copper (Cu) and antimony (Sb) (SnBiCuSb), tin (Sn) and silver (Ag) ) And an alloy of bismuth (Bi) (SnAgBi), an alloy of tin (Sn) and indium (In) (SnIn), an alloy of tin (Sn), indium (In) and bismuth (Bi) (SnInBi), Alternatively, another alloy having a melting point relatively low as compared with the softening point of the base material 2 and other combinations of bismuth (Bi) and / or indium (In) can be used, for example, as the base material 2. It is desirable to have a melting point of 120-140 ° C., which is lower than the softening point of polyethylene terephthalate (PET).

By using a solder paste having a melting point lower than the softening point of the base material 2, the base material 2 does not melt or otherwise deform, while the solder paste melts and chemically and physically with the metal wiring pattern 3. It is ready to be joined. Then, the solder solidifies, and the external connection terminal 4 is joined to the metal wiring pattern 3 via the solder 5A.

Further, laser soldering or light firing soldering may be used for joining the external connection terminal 4 and the metal wiring pattern 3. In this case, as compared with trowel soldering, the base material 2 is not subjected to a load in a non-contact manner. Therefore, the solder is not limited to low temperature solder, and may be ordinary solder.

As shown in FIG. 2B, the joining member 5 may be a conductive wire rod 5B. The conductive wire 5B is a conducting wire that electrically connects the anchor portion 4b of the external connection terminal 4 and the metal wiring pattern 3 by wire bonding, and specifically, gold, copper, silver, platinum, aluminum, or these. Metal wire of the alloy of the above can be used. In particular, a gold wire that is less likely to break due to stress from the coating material described later and has excellent thermal resistance is preferable.

(Resin layer)
The resin layer 6 is formed on one surface 2a of the base material 2 via the adhesive layer AD so that the terminal portion 4a of the external connection terminal 4 is exposed, and the metal wiring pattern 3 is arranged as shown in FIG. It is configured to include a main body portion 61 that covers one side 2a, and a housing portion 62 that has a tubular shape and surrounds the terminal portion 4a of the external connection terminal 4 so as to be exposed inside the cylinder. In the electronic device 1 according to the present embodiment, the external connection terminal 4 and the housing portion 62 form a connector for electrically connecting the electronic device 1 and an external element provided outside the electronic device 1.
As a result, the number of parts can be reduced and the external connection terminal 4 can be arranged with high positional accuracy on the metal wiring pattern 3 formed on the deformable base material 2. The adhesive layer AD is preferably toned so as to cover the metal wiring pattern 3.

The resin layer 6 may also be formed on the other surface 2b on the side opposite to the one surface 2a on which the metal wiring pattern 3 of the base material 2 is arranged. The resin layer 6 formed on the other surface 2b may be the same resin material as the resin layer 6 formed on the one surface 2a, but may be a different resin material. The resin layer 6 formed on the other surface 2b is formed by making the adhesive layer AD translucent and using the resin material as a transparent resin material, for example, when the inside of the electronic device 1 is decorated. It can be made visible while protecting the decoration. Here, from the usage mode, a resin layer 6 composed of a main body portion 61 that covers one surface 2a of the base material 2 and a housing portion 62 that surrounds the external connection terminal 4 so that the terminal portion 4a of the external connection terminal 4 is exposed is formed. The side that has been formed is the back side of the electronic device 1, and the side on which the resin layer 6 made of the transparent resin material is formed is the front side of the electronic device 1 as the decorative side.

The resin layer 6 is a thermoplastic resin made of a thermoplastic resin material that can be secondarily molded. Specifically, polycarbonate (PC), polyethylene terephthalate (PET), polymethylmethacrylate (PMMA), polyamide (PA), acrylic 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. A plastic resin can be used.

As shown in FIG. 3, the resin layer 6 may be formed on the other surface 2b on the side opposite to the one surface 2a on which the metal wiring pattern 3 of the base material 2 is arranged. In this case, as shown in FIG. 3B, the metal wiring pattern 3 and the metal wiring pattern 3 of the electronic device 1 are formed by forming the resin layer 6 on the one surface 2a on which the metal wiring pattern 3 of the base material 2 is arranged. It is possible to cover and protect the electronic components attached to the.

(Coating layer)
The coating layer 7 is arranged in the recess 8 by potting so as to cover the upper surface in a state where the external connection terminal 4 and the metal wiring pattern 3 are joined by the joining member 5, and protects the joining member 5. As shown in FIG. 2, the recess 8 is formed as a region in which the resin layer 6 is not formed when the resin layer 6 is secondarily molded. Further, as shown in FIG. 3, when the base material 2 and the external connection terminal 4 are placed on a mold and the resin layer 6 is secondarily molded, the base material 2 is thermoformed by the mold. It may be formed by.

As the resin material used for the coating layer 7, a curable resin made of a thermosetting resin material, a two-component curable resin material, a photocurable resin material, or a moisture-curable resin material is preferable. Specifically, various resins such as epoxy resin, urethane resin, acrylic resin, polyimide resin, polyamide resin, bismaleimide, phenol resin, polyester resin, silicone resin, and oxetane resin can be used. Among these, epoxy resin is particularly preferable. These curable resins may be used alone or in combination of two or more.

The viscosity of the resin material used for the coating layer 7 is preferably 0.3 Pa · s or more and 15 Pa · s or less at room temperature (20 ± 5 ° C.). When the viscosity of the resin material fat is 0.3 Pa · s or more, the resin material can be easily arranged so as to fill the recess 8 formed by potting.
These curable resin materials are also used as adhesives and paints, have high adhesion to various materials, and have low viscosity in the state of the monomer before curing, so they are excellent in moldability and external connection terminals. It is suitable for covering the entire joining member 5 that joins the anchor portion 4b of 4 and the metal wiring pattern 3.

(2) Manufacturing Method of Electronic Device FIG. 4 is a flowchart showing an example of a schematic procedure of the manufacturing method of the electronic device 1, and FIG. 5 is a schematic partial cross-sectional view of the electronic device 1 for explaining the manufacturing process of the electronic device 1. FIG. 6 is a schematic partial cross-sectional view of the electronic device 1 for explaining another manufacturing process of the electronic device 1.
The electronic device 1 includes a base layer forming step S1 in which a catalyst ink such as metal nanoparticles is applied onto a thermoforming base material 2 made of a thermoplastic resin, and metal wiring on the base layer 3a by plating. The plating step S2 for forming the pattern 3, the base material 2 on which the metal wiring pattern 3 is arranged, and the external connection terminal 4 are placed on a mold, and the thermoplastic resin is injection-molded so as to cover at least one surface of the base material 2. Is manufactured through a resin filling step S3 for secondary molding and an electrical joining step S4 for electrically joining the metal wiring pattern 3 and the external connection terminal 4 with the joining member 5.

(Underground layer forming process)
In order to arrange the metal wiring pattern 3 on the substantially flat film-like base material 2 formed into a predetermined shape and size, metal nanoparticles or the like that trigger the growth of metal plating on the base material 2 The base layer 3a made of catalyst particles is formed in a predetermined pattern. The base material 2 is preferably subjected to surface treatment such as corona treatment, plasma treatment, solvent treatment, and primer treatment in order to uniformly apply the catalyst ink composed of catalyst particles such as metal nanoparticles.

As a method of applying a catalyst ink composed of catalyst particles such as metal nanoparticles on the base material 2, an inkjet printing method, a silk screen printing method, a gravure printing method, an offset printing method, a flexo printing method, a roller coater method, and brush coating are used. Methods, spray method, knife jet coater method, pad printing method, gravure offset printing method, die coater method, bar coater method, spin coater method, comma coater method, impregnation coater method, dispenser method, metal mask method, etc. In this embodiment, an inkjet printing method is used.

Specifically, after applying a low-viscosity catalyst ink of 1000 cps or less, for example, 2 cps to 30 cps by an inkjet printing method, the solvent is volatilized to leave only metal nanoparticles. Then, the solvent is removed (drying) and the metal nanoparticles are sintered (baking).
The firing temperature is preferably 100 ° C to 300 ° C, more preferably 150 ° C to 200 ° C. If the firing temperature is too low, the sintering of the metal nanoparticles will be insufficient, and components other than the metal nanoparticles will remain, so that adhesion may not be obtained. Further, if the firing temperature is too high, the base material 2 may be deteriorated or distorted.

The content ratio of the metal nanoparticles in the catalyst ink is preferably 5% to 60%, more preferably 10% to 30% in terms of mass ratio. If the content ratio is too low, there is a risk that the nanoparticles required to form the base layer 3a made of metal nanoparticles will be insufficient and pinholes will occur, and if the content ratio is too high, the particles will easily aggregate in the ink. There is a risk that stability will be impaired.

(Plating process)
By performing electrolytic plating or electroless plating on the base layer 3a formed on the base material 2 through the base layer forming step, plating metal is deposited on the surface and inside of the base layer 3a. The plating method is the same as that of known plating solutions and plating treatments, and specific examples thereof include electrolytic copper plating and electrolytic copper plating.

(Resin filling process)
In the resin filling step S3, first, as shown in FIG. 5A, the other surface on the opposite side of the one side 2a on which the metal wiring pattern 3 of the base material 2 on which the metal wiring pattern 3 is arranged is arranged in the plating step S2. After applying the binder ink Ba to 2b, the resin layer 6 is formed by a secondary mold. The binder ink Ba contains an adhesive resin and is applied by screen printing, inkjet printing, spray coating, brush coating or the like to improve the adhesiveness between the base material 2 and the second-molded resin layer 6. When the resin layer 6 made of a transparent resin material is formed, it is preferably translucent.

Next, after the binder ink Bb is applied to the one surface 2a on which the metal wiring pattern 3 of the base material 2 is arranged, the resin layer 6 is formed on the other surface 2b of the base material 2 as shown in FIG. 5 (b). The base material 2 and the external connection terminal 4 are positioned and placed on the mold for secondary molding, the mold is closed, and the thermoplastic resin is injection-molded so as to cover one surface 2a of the base material 2. Here, the binder ink Bb is preferably toned so as to cover the metal wiring pattern 3. As a result, the metal wiring pattern 3 can be made invisible from the back surface side of the electronic device 1 on which the resin layer 6 is arranged, and the appearance can be maintained.

In this resin filling step S3, the thermoplastic resin is injected by injection molding with the mold and the external connection terminal 4 positioned, and the main body 61 covering the one surface 2a on which the metal wiring pattern 3 is arranged and the outside A resin layer 6 is formed in which the housing portion 62 surrounding the external connection terminal 4 is integrated so that the terminal portion 4a of the connection terminal 4 is exposed.
In this way, the resin layer 6 is secondarily molded with the base material 2 on which the external connection terminal 4 and the metal wiring pattern 3 are arranged positioned and placed on the mold, thereby reducing the number of parts and deforming. The external connection terminal 4 can be arranged with high positional accuracy on the metal wiring pattern 3 formed on the possible base material.

In the resin filling step S3, as shown in FIG. 6, the base material 2 in which the metal wiring pattern 3 is arranged on one surface 2a and the external connection terminal 4 are positioned and placed on the secondary molding die. In this state, the thermoplastic resin is injection-molded so as to cover the other surface 2b on the side opposite to the one surface 2a of the base material 2 (see FIG. 6A), and the main body 61 covering the other surface 2b and the external connection terminal. The resin layer 6 in which the housing portion 62 surrounding the 4 is integrated may be formed first. After that, the metal wiring pattern 3 and the external connection terminal 4 are joined with the solder 5A, the solder 5A is covered with the coating layer 7 by potting (see FIG. 6B), and the one surface 2a on which the metal wiring pattern 3 is arranged is covered. The resin layer 6 may be secondarily molded as described above (see FIG. 6C).

Further, in the resin filling step S3, as shown in FIG. 3, the base material 2 and the external connection terminal 4 are placed on the mold, and the metal wiring pattern 3 and the external connection terminal 4 are connected by the joining member 5. The recess 8 may be shaped by thermoforming. In the joining step S4 described later, the curable resin material is potted in the recess 8 to form the coating layer 7. As a result, the recess 8 in which the coating layer 7 is arranged can be integrally formed with the resin layer 6.

(Electrical joining process)
In order to join the external connection terminal 4 on the metal wiring pattern 3 formed on the base material 2 with the solder 5A as the joining member 5, solder paste is applied to the metal wiring pattern 3 and the anchor portion 4b of the external connection terminal 4. To do. The solder paste can be applied using a known device such as a stencil printing device, a screen printing device, or a dispenser device. In this embodiment, the solder paste is applied using a dispenser device.

After applying the solder paste on the metal wiring pattern 3 and the anchor portion 4b of the external connection terminal 4 by the dispenser device, as shown in FIG. 5C, the solder is melted and solidified, and the solder 5A is placed on the metal wiring pattern 3. The anchor portion 4b of the external connection terminal 4 is electrically joined via the solder. For example, the base material 2 made of a thermoplastic resin that can be deformed by thermoforming or the like has a low softening point, but by soldering with a low-temperature solder to the solder, the base material 2 is heated by the electrical joining process. Does not melt or otherwise deform.

Further, as the soldering, laser soldering or light firing soldering may be used. In this case, the solder is not limited to low-temperature solder, and may be ordinary solder because it is non-contact and does not give a load to the base material 2.

In the electrical bonding step S4, the metal wiring pattern 3 and the external connection terminal 4 may be electrically and mechanically bonded by a wire bonding method using ultrasonic waves with a conductive wire rod as a bonding member 5 (FIG. 6). 2 (b)). A gold wire, an aluminum wire, or the like can be used as the conductive wire, but by using an aluminum wire containing aluminum as a main component, the base material 2 is melted or deformed by the heat at the time of wire bonding. Can be suppressed.

After joining with the joining member 5, as shown in FIG. 5D, an uncured curable resin material is potted (resin-filled) in the recess 8 formed in the resin filling step S3 to form the metal wiring pattern 3 and The external connection terminal 4 and the joining member 5 are integrally covered to form the coating layer 7.
The method for curing the uncured coating layer 7 formed by potting is not particularly limited as long as the curable resin material can be cured, and can be appropriately selected depending on the type of resin used. In the present embodiment, the base material 2 is melted by using a two-component curable resin material, a photocurable resin material, or a moisture-curable resin material that does not require heating for curing as the curable resin material. It is possible to suppress the deformation and deformation. ..

According to the electronic device 1 according to the present embodiment, the number of parts can be reduced and the external connection terminal 4 can be arranged with high position accuracy on the metal wiring pattern 3 formed on the deformable base material 2. The external connection terminal 4 and the metal wiring pattern 3 arranged with high positional accuracy are soldered with solder 5A or wire-bonded via a conductive wire rod 5B to be joined.

FIG. 7 is a schematic partial cross-sectional view of the electronic device 1 for explaining another manufacturing process of the electronic device 1, and FIG. 8 is a schematic partial cross-sectional view showing another aspect of the electronic device 1.
According to the manufacturing method of the electronic device 1 according to the present embodiment, as shown in FIG. 7, the resin layer 6 is secondarily molded on the base material 2 on which the metal wiring pattern 3 is arranged, and the other surface of the base material 2 is formed. After forming a resin layer 6 in which the main body 61 and the housing 62 surrounding the external connection terminal 4 are integrated on 2b (see FIG. 7A), the external connection terminal 4 is inserted into the housing 62. It may be press-fitted into the hole 6a and electrically joined to the metal wiring pattern 3 with the solder 5A (see FIG. 7B). The insertion hole 6a into which the external connection terminal 4 is inserted is formed integrally with the housing portion 62 by a secondary mold, and the external connection terminal 4 can be arranged with high positional accuracy.

The solder 5A may be covered with the coating layer 7, and the resin layer 6 may be secondarily formed so as to cover one surface 2a of the base material 2 if necessary (see FIG. 7C).

Further, as shown in FIG. 8, the resin layer 6 is secondarily molded in a state where the base material 2 on which the external connection terminal 4 and the metal wiring pattern 3 are arranged is positioned and placed on the mold. As shown by the arrow of, the anchor portion 62 of the external connection terminal 4 and the metal wiring pattern 3 may be brought into close contact with each other by a secondary molded resin pressure and electrically joined. The anchor portion 62 may be provided with a flexible shape having a spring property in advance to improve the electrical connection with the metal wiring pattern 3. As a result, the number of parts can be further reduced without using the joining member 5 for electrical joining between the metal wiring pattern 3 and the external connection terminal 4, and the metal wiring pattern 3 formed on the deformable base material 2 can be used. The external connection terminal 4 can be arranged with high positional accuracy.

1 ... Electronic device 2 ... Base material 3 ... Metal wiring pattern 4 ... External connection terminal 4a ... Terminal part 4b ... Anchor part 5 ... Joining member 5A ... Solder 5B・ ・ ・ Wire material 6 ・ ・ ・ Resin layer 7 ・ ・ ・ Coating layer

Claims (5)

A base material made of synthetic resin material that can be transformed from a substantially flat two-dimensional shape to a substantially three-dimensional shape,
The metal wiring pattern arranged on the base material and
The base material is thermoformed to come into contact with the metal wiring pattern at a recess shaped into the three-dimensional shape in the thickness direction of the base material, and an external element provided outside the base material is electrically connected. With an external connection terminal for connecting to
A housing that surrounds the external connection terminal is formed so that the terminal surface, which is the surface of the external connection terminal, is exposed, and a resin layer that covers at least one surface of the base material is formed.
A joining means for electrically joining the metal wiring pattern and the external connection terminal in the recess,
The recess is filled with the metal wiring pattern and a coating layer that integrally covers the external connection terminal and the joining means.
An electronic device characterized by that. The resin layer is formed on one surface of the base material via a toned adhesive layer that makes the metal wiring pattern invisible from the outside.
The electronic device according to claim 1. The resin layer is formed of a transparent resin material on the other surface opposite to one surface of the base material via a translucent adhesive layer.
The electronic device according to claim 1 or 2. A base material made of synthetic resin material that can be transformed from a substantially flat two-dimensional shape to a substantially three-dimensional shape,
The metal wiring pattern arranged on the base material and
The base material is thermoformed to come into contact with the metal wiring pattern at a recess shaped into the three-dimensional shape in the thickness direction of the base material, and an external element provided outside the base material is electrically connected. With an external connection terminal for connecting to
A housing that surrounds the external connection terminal is formed so that the terminal surface, which is the surface of the external connection terminal, is exposed, and a resin layer that covers at least one surface of the base material is formed.
A joining means for electrically joining the metal wiring pattern and the external connection terminal in the recess,
A method of manufacturing an electronic device including a coating layer that fills the recess and covers the joining means.
The process of preparing the base material and
The step of arranging the metal wiring pattern on the base material and
A step of positioning and placing the base material on which the metal wiring pattern is arranged and the external connection terminal on a mold to shape the recess and at the same time injection molding the resin layer.
A process of electrically joining the metal wiring pattern and the external connection terminal by a joining means,
A coating step of filling the recess with the coating layer and integrally covering the metal wiring pattern, the external connection terminal, and the joining means is executed in order.
A method for manufacturing an electronic device. A base material made of synthetic resin material that can be transformed from a substantially flat two-dimensional shape to a substantially three-dimensional shape,
The metal wiring pattern arranged on the base material and
The base material is thermoformed to come into contact with the metal wiring pattern at a recess shaped into the three-dimensional shape in the thickness direction of the base material, and an external element provided outside the base material is electrically connected. With an external connection terminal for connecting to
A housing that surrounds the external connection terminal is formed so that the terminal surface, which is the surface of the external connection terminal, is exposed, and a resin layer that covers at least one surface of the base material is formed.
A joining means for electrically joining the metal wiring pattern and the external connection terminal in the recess,
A method of manufacturing an electronic device including a coating layer that fills the recess and covers the joining means.
The process of preparing the base material and
The step of arranging the metal wiring pattern on the base material and
The base material on which the metal wiring pattern is arranged is positioned and placed on a mold to form the recess, and at the same time, the base material is covered on the other surface opposite to the one on which the metal wiring pattern is arranged. The process of injection molding the resin layer and
A process of electrically joining the metal wiring pattern and the external connection terminal by a joining means,
A coating step of filling the recess with the coating layer to integrally cover the metal wiring pattern, the external connection terminal, and the joining means.
The steps of injection molding the resin layer so as to cover one surface on which the metal wiring pattern is arranged are executed in order.
A method for manufacturing an electronic device.

Images