JP5403270B2 - CIRCUIT BOARD DEVICE, BOARD, CIRCUIT BOARD DEVICE MANUFACTURING METHOD, ELECTRONIC DEVICE - Google Patents

Description

  The present invention relates to a circuit board device, a substrate, a method for manufacturing the circuit board device, and an electronic apparatus.

  In many electronic devices such as mobile phone devices and PDA (Personal Digital Assistant) terminals, a plurality of printed wiring boards, functional parts, and the like are mounted in a limited space. The printed wiring board is, for example, a board on which many printed electronic components are mounted. Examples of the functional components include a display device represented by a liquid crystal display (LCD) and an organic EL display (OELD), a keyboard, a camera, a speaker, and a microphone.

  Particularly in recent years, electronic devices have become more sophisticated and multifunctional. For this reason, it is required to electrically connect a plurality of printed wiring boards having a large number of connection terminals. In addition, there is a demand for both a reduction in size and thickness. In response to these requirements, the pitch of electrode patterns on printed circuit boards is being reduced. Along with the narrowing of the electrode pattern, the connection terminals between the printed wiring boards are also narrowed. Correspondingly, an electrical connection structure using an anisotropic conductive material is used. This electrical connection structure is more suitable for electrical connection between connection terminals having a narrower pitch than the conventional electrical connection structure using solder. The anisotropic conductive material is, for example, a mixture of conductive particles in a binder such as acrylic, epoxy, polyimide, or silicone. Examples of the anisotropic conductive material include an anisotropic conductive film (ACF: Anisotropic Conductive Film) and an anisotropic conductive paste (ACP: Anisotropic Conductive Paste). An electrical connection structure using an anisotropic conductive material is disclosed in, for example, Non-Patent Document 1 or Patent Document 1.

  Non-Patent Document 1 discloses an electrical connection structure (circuit board device) between a membrane switch and an LCD. The cross-sectional view of FIG. 7 shows the configuration of this circuit board device. In this circuit board device 700, the conductive particles 707 are sandwiched between the counter electrodes 703 and 704 provided on the glass substrate 701 and the PET base material 702 of the LCD 708 so as to be electrically connected (electrically connected). . The anisotropic conductive material 705 includes a binder 706 and conductive particles 707. Such electrical connection is performed by expanding the binder by heating and pressing and sandwiching at least one conductive particle between the counter electrodes.

  Patent Document 1 discloses that an input pad (connection terminal) of a tape carrier package and a wiring pattern of a printed board are connected by an anisotropic conductive film. In Patent Document 1, examples of the shape of the input pad include a circle, an ellipse, and a polygon. Further, it is described that input pads having these shapes are arranged in a staggered manner between adjacent ones (claim 2, 0034 paragraph, etc. of the same document).

  As described above, the anisotropic conductive material (ACF or ACP) includes, for example, a binder such as acrylic, epoxy, polyimide, silicone, and conductive particles. In order to ensure electrical connection between the counter electrodes (connection terminals), as described above, it is said that one or more conductive particles must remain in the gap between the pair of connection terminals. The anisotropic conductive material defines a minimum overlap area for preventing the number of conductive particles remaining in the gap between the pair of connection terminals from being less than one. In addition, an overlap area means the area of the part which the connection terminals electrically connected overlap, for example.

  Here, in the circuit board device, there is a positioning tolerance caused by various factors, for example, in positioning between boards such as a printed wiring board having a pair of connection terminals. For this reason, a certain positional deviation usually occurs between the connection terminals. Therefore, a proposal has been made to reduce the positioning tolerance, that is, to perform positioning accurately (see, for example, Patent Document 2).

  As shown in FIGS. 8A, 8E, and 8F, the circuit board device described in Patent Document 2 has connection terminals 803 made of electrodes and positioning terminals 805a and 805b. It has a first substrate 801 and a second substrate 802 on which connection terminals 804 made of electrodes and positioning terminals 806a and 806b are formed. The connection terminals 803 and 804 have a rectangular shape and are arranged in a line in the pitch direction. The positioning terminals 805a and 805b are formed in the vicinity of both ends of the first substrate 801. The positioning terminals 806a and 806b are formed in positions near the both ends of the second substrate 802 and facing the positioning terminals 805a and 805b. A thermoplastic joining member 807 is formed on the positioning terminals 805a and 805b. The ACF 808 is mounted on the connection terminal 804 of the second substrate 802.

  The circuit board device 800 is manufactured as follows. First, as shown in FIG. 8B, the thermoplastic joining member 807 is selectively melted using a local heater 809. Next, as shown in FIG. 8C, the connection location where the connection terminal 803 and the connection terminal 804 on which the ACF 808 is mounted is heated and pressurized using a thermocompression bonding tool 810, The connection terminal 804 is electrically and mechanically connected (FIG. 8D). The external dimensions in the terminal pitch direction of the thermocompression bonding tool 810 are set shorter than between the positioning terminals 805a and 805b and between 806a and 806b. The circuit board device 800 can be accurately positioned by the self-alignment effect due to the surface tension when the thermoplastic bonding member 807 is melted.

JP-A-8-166596 JP 2006-319053 A

“Anisotropic conductive material connection”, Fujikura Technical Report, No.99, October 2000, p. 32-38

  In the circuit board device described in Patent Document 2, positioning can be performed accurately, that is, positioning tolerance can be reduced. However, in the circuit board device described in Patent Document 2, even if it is within the range of positioning tolerance, it is not possible to reduce the fluctuation itself of the overlap area due to the generated positional deviation between the connection terminals. As a result, the fluctuation of the number of trapped conductive particles increases, and for example, a stable electric resistance value cannot be obtained. In addition, for example, the probability that an open defect will occur increases when the number of trapped conductive particles is less than one.

  An object of the present invention is to provide a circuit board device that can reduce fluctuations in the overlap area between connection terminals due to misalignment.

In order to achieve the above object, a circuit board device of the present invention comprises:
A first substrate and a second substrate facing each other;
The first substrate has a plurality of first connection terminals arranged on a surface facing the second substrate,
The second substrate has a plurality of second connection terminals arranged on a surface facing the first substrate,
Each of the first connection terminals is arranged such that a planar shape thereof is a polygon and at least one corner of the polygon is oriented in a direction y orthogonal to the arrangement direction x;
Each of the second connection terminals has the same planar shape as the first connection terminal, and the position of each of the second connection terminals has a one-to-one correspondence with each of the first connection terminals. Are arranged as
By arranging an anisotropic conductive material between the first connection terminal and the second connection terminal, the first substrate and the second substrate are electrically connected,
A cosine which is an acute angle formed by a straight line in a misalignment direction and a straight line in the arrangement direction x, which is calculated from a positioning accuracy value in the arrangement direction x and a positioning accuracy value in a direction y orthogonal to the arrangement direction x. The angle θ of the angle directed in the direction y with respect to the angle Φ of the angle satisfies the relationship of the following formula (1).

θ = 180 ° -2 × Φ (1)

The substrate of the present invention is
Used in the circuit board device of the present invention,
It has a plurality of connection terminals on one side,
Each of the connection terminals is arranged such that the planar shape thereof is a polygon and at least one corner of the polygon faces a direction y orthogonal to the arrangement direction x.
A cosine which is an acute angle formed by a straight line in a misalignment direction and a straight line in the arrangement direction x, which is calculated from a positioning accuracy value in the arrangement direction x and a positioning accuracy value in a direction y orthogonal to the arrangement direction x. The angle θ of the angle directed in the direction y with respect to the angle Φ of the angle satisfies the relationship of the formula (1).

In addition, the method for manufacturing the circuit board device of the present invention includes:
A substrate preparation step of preparing a first substrate having a plurality of first connection terminals arranged on one surface and a second substrate having a plurality of second connection terminals arranged on one surface; ,
An anisotropic conductive material is sandwiched between the first connection terminal and the second connection terminal, and the anisotropic is applied between the first connection terminal and the second connection terminal by heating and pressing. An electrical connection step of electrically connecting the first substrate and the second substrate by disposing a conductive material;
Each of the first connection terminals is arranged such that a planar shape thereof is a polygon and at least one corner of the polygon is oriented in a direction y orthogonal to the arrangement direction x;
Each of the second connection terminals has the same planar shape as the first connection terminal, and the position of each of the second connection terminals has a one-to-one correspondence with each of the first connection terminals. Are arranged as
A cosine which is an acute angle formed by a straight line in a misalignment direction and a straight line in the arrangement direction x, which is calculated from a positioning accuracy value in the arrangement direction x and a positioning accuracy value in a direction y orthogonal to the arrangement direction x. With respect to the angle angle Φ, the angle angle θ directed in the direction y satisfies the relationship of the following formula (2).

θ = 180 ° -2 × Φ (2)

The electronic device of the present invention is
The circuit board device according to the present invention or the circuit board device manufactured by the manufacturing method according to the present invention is provided.

  ADVANTAGE OF THE INVENTION According to this invention, the circuit board apparatus which can reduce the fluctuation | variation of the overlap area between the connection terminals by position shift, a board | substrate, the manufacturing method of a circuit board apparatus, and an electronic device can be provided.

(A) is a top view which shows the structure of an example of Embodiment 1 in the circuit board apparatus of this invention. (B) is sectional drawing seen in the II direction of the circuit board apparatus shown to Fig.1 (a). (C) is the top view to which the connection part of the area | region enclosed with the dashed-two dotted line of the circuit board apparatus shown to Fig.1 (a) was expanded. (D) is a figure which shows the position shift direction in the said example. (E) is a figure which illustrates the definition of a cosine angle. (A) is a top view which shows the structure of the circuit board apparatus used for the comparison. (B) is the top view to which the connection part of the area | region enclosed with the dashed-two dotted line of the circuit board apparatus shown to Fig.2 (a) was expanded. It is a perspective view which shows 1 process of the manufacturing method of the circuit board apparatus shown to Fig.1 (a). (A) is a top view which shows the structure of an example of Embodiment 2 in the circuit board apparatus of this invention. (B) is the top view to which the connection part of the area | region enclosed with the dashed-two dotted line of the circuit board apparatus shown to Fig.4 (a) was expanded. (C) is a figure which shows the position shift direction in the said example. (A) is a top view which shows the structure of the other example of the said Embodiment 1. FIG. (B) is a top view which shows the structure of the other example of the said Embodiment 2. FIG. (C) is a top view which shows the structure of the modification in the circuit board apparatus of this invention. (A) is a top view which shows the structure of an example of Embodiment 3 in the circuit board apparatus of this invention. (B) is the top view to which the connection part of the area | region enclosed with the dashed-two dotted line of the circuit board apparatus shown to Fig.6 (a) was expanded. (C) is a figure which shows the position shift direction in the said example. It is sectional drawing which shows the structure of the electrical-connection structure (circuit board apparatus) of a nonpatent literature 1. It is a figure which shows the structure and manufacturing method of the circuit board apparatus of patent document 2. FIG.

  In the present invention, the “cosine angle” is a straight line in a misalignment direction calculated from a positioning accuracy value in the arrangement direction x and a positioning accuracy value in a direction y orthogonal to the arrangement direction x, and the arrangement An acute angle with a straight line in the direction x. For example, as shown in FIG. 1 (e), the origin O (0, 0), the point X (x, 0) on the x axis, the point Y (0, y) on the y axis orthogonal to the x axis, It is assumed that the point Z (x, y) is calculated from the point X and the point Y. In this case, in a right triangle formed by the origin O, the point Z, and the point X and having a right angle formed by the side ZX and the side OX, the angle formed by the side ZO and the side OX is a cosine angle. is there. The direction of the side OX in the figure corresponds to the “array direction x” in the present invention. The direction of the side OY in the figure corresponds to the “direction y orthogonal to the arrangement direction x” in the present invention. The direction from the origin O to the point Z in the figure corresponds to the “positional deviation direction” in the present invention.

  Hereinafter, the circuit board device, the method for manufacturing the circuit board device, the board, and the electric device of the present invention will be described in detail with examples. However, the present invention is not limited to the following embodiments. In addition, in the following FIGS. 1-8, the same code | symbol is attached | subjected to the same part. In the drawings, for convenience of explanation, the structure of each part may be simplified as appropriate, and the dimensional ratio of each part may be different from the actual one.

(Embodiment 1)
FIG. 1 shows an example of the configuration of the circuit board device of the present embodiment. FIG. 1A is a plan view of the circuit board device of the present embodiment. FIG.1 (b) is sectional drawing seen in the II direction of Fig.1 (a). FIG. 1C is an enlarged plan view of a connection portion of a region 110 surrounded by a two-dot chain line of the circuit board device shown in FIG. FIG. 1 (d) is a diagram showing a misalignment direction in the circuit board device of the present embodiment. As illustrated, the circuit board device 100 includes a first printed wiring board 101 and a second printed wiring board 102 that face each other. The first printed wiring board 101 is a rigid printed wiring board having FR4 as a base material. The second printed wiring board 102 is a flexible printed wiring board based on polyimide. The “first printed wiring board” in the present embodiment corresponds to the “first board” of the present invention. The “second printed wiring board” in the present embodiment corresponds to the “second board” of the present invention.

  The first printed wiring board 101 has a plurality of first connection terminals 103 for signal connection arranged on a surface facing the second printed wiring board 102 (upper surface in FIG. 1B). . A signal wiring pattern is drawn out from the first connection terminal 103 and is electrically connected to an electric circuit and an electric circuit component on the first printed wiring board 101 (not shown). The second printed wiring board 102 has a plurality of second connection terminals 104 arranged on the surface facing the first printed wiring board 101 (the lower surface in FIG. 1B). A signal wiring pattern is drawn out from the second connection terminal 104 and is electrically connected to an electric circuit and an electric circuit component on the second printed wiring board 102 (not shown).

An anisotropic conductive film (ACF: Anisotropic Conductive Film) 105 is disposed between the first connection terminal 103 and the second connection terminal 104. Thereby, the first printed wiring board 101 and the second printed wiring board 102 are electrically connected. ACF 105 is a film (thickness: 20 μm) in which 10% by weight of conductive particles (metal particles) made of Ni having a diameter of 12 μm are blended in a resin (binder) whose main raw material is an epoxy resin. The ACF 105 is preliminarily processed in accordance with the shapes of the first connection terminal 103 and the second connection terminal 104. In this ACF 105, the minimum overlap area for preventing the number of trapped conductive particles from being less than 1 is 0.050 mm ² . The “anisotropic conductive film” in this embodiment corresponds to the “anisotropic conductive material” in the present invention.

  The planar shapes of the first connection terminals 103 are all hexagons having the same shape. The first connection terminals 103 are arranged in a staggered pattern in one direction of the surface of the first printed wiring board 101 (arrangement direction x). The hexagons are arranged so that the opposite corners a in the staggered arrangement are oriented in a direction y that is orthogonal to the arrangement direction x on a plane.

In the circuit board device according to the present embodiment, for example, the positioning accuracy value dx in the arrangement direction x of the first connection terminals 103 is 0.100 mm by a manufacturing method described later. Further, for example, by a manufacturing method described later, the positioning accuracy value dy in the direction y perpendicular to the arrangement direction x of the first connection terminals 103 is 0.050 mm. From the positioning accuracy value dx in the direction x and the positioning accuracy value dy in the direction y, as shown in FIG. An angle Φ of a cosine angle that is an acute angle formed by the straight line in the displacement direction ds and the straight line in the direction x is 26.565 °. The angle θ1 of the angle a, which is the angle that faces the hexagonal direction y that is the planar shape of each first connection terminal 103, is set so as to satisfy the following expression (3) with respect to this angle Φ. . The angle θ1 is 126.870 °. The “angle θ1” in the present embodiment corresponds to the “angle θ” in the present invention.

θ1 = 180 ° −2 × Φ (3)

An angle b, which is an angle located at two angles with respect to the angle a in the hexagon (the first connection terminal 103), is directed to the direction y. The angle θ1 of the angle a and the angle θ2 of the angle b are equal (θ1 = θ2 = 126.870 °). In each hexagon, the width L1 is 0.339 mm. Its length H1 is 0.380 mm. The area A is 0.100 mm ² . The equivalent pitch Px in the arrangement direction x is 0.245 mm.

  The planar shape of each second connection terminal 104 is the same as that of the first connection terminal 103, and the position of each second connection terminal 104 has a one-to-one correspondence with each first connection terminal 103. Is arranged. Note that in FIG. 1C, each second connection terminal 104 is indicated by a two-dot chain line in consideration of easy viewing. In FIG. 1C, the description of the first substrate 101 and the anisotropic conductive film 105 is omitted. The same applies to Embodiments 2 and 3 described later.

  In the present invention, a mechanism capable of reducing fluctuations in the overlap area between connection terminals due to misalignment will be described using this embodiment in comparison with the circuit board device shown in FIG. FIG. 2A is a plan view showing a configuration of a circuit board device used for comparison. FIG. 2B is an enlarged plan view of a connection portion of a region 110 ′ surrounded by a two-dot chain line of the circuit board device shown in FIG.

In the circuit board device shown in FIG. 2, the planar shapes of the plurality of first connection terminals 103 ′ are all rectangular (rectangular) having the same shape. The first connection terminals 103 ′ are arranged in a line in the same direction as the arrangement direction x of the first connection terminals 103 in the present embodiment. In each of the rectangles, the width L2 is 0.150 mm. Its length H2 is 0.667 mm. The area B is 0.100 mm ² . The equivalent pitch Px in the arrangement direction x is 0.300 mm.

  The planar shape of each second connection terminal 104 ′ is the same as that of the first connection terminal 103 ′, and the position of each second connection terminal 104 ′ is one-to-one with each first connection terminal 103 ′. Are arranged to correspond. Other configurations are the same as those of the circuit board device 100 of the present embodiment. In FIG. 2B, each of the second connection terminals 104 'is indicated by a two-dot chain line in consideration of easy viewing. In FIG. 2B, the description of the first substrate 101 and the anisotropic conductive film 105 is omitted.

In the circuit board device according to the present embodiment, the overlap area A ′ between the first connection terminal 103 and the second connection terminal 104 due to the displacement between the connection terminals is 0.062 mm ² . Since it is more than the minimum overlap area (0.050 mm < ² >) of the anisotropic conductive film 105, the open defect resulting from the above-mentioned insufficient number of conductive particle capture does not occur.

On the other hand, in the circuit board device shown in FIG. 2, the overlap area B ′ between the first connection terminal 103 ′ and the second connection terminal 104 ′ due to the displacement between the connection terminals is 0.031 mm ² . Since it is less than the minimum overlap area (0.050 mm < ² >) of the anisotropic conductive film 105, possibility that the open defect resulting from the above-mentioned insufficient conductive particle capture number will become very high.

  Although the area of each connection terminal in both the circuit board devices is the same, the fluctuation of the overlap area with respect to the same direction and the same value of the position shift is smaller in the circuit board device of this embodiment. This is because, in the circuit board device of the present embodiment, the corners a of the respective connection terminals are arranged so as to be directed in a direction y orthogonal to the arrangement direction x, and the angle θ1 of the corner a is the aforementioned. This is because the angle Φ is set at an angle (θ1 = 126.870 °) satisfying the expression (3). By doing so, the direction of one side forming the corner a (the right side in FIG. 1C) coincides with the misalignment direction. For this reason, the fluctuation | variation of the overlap area between connection terminals by position shift can be reduced. As described above, in the present invention, a polygon (for example, a hexagon) is not simply selected as the shape of the connection terminal, but an angle is set in accordance with the misalignment direction between the connection terminals in the circuit board device. A square is selected. For this reason, according to this invention, the fluctuation | variation of the overlap area between connection terminals can be reduced according to the position shift for every circuit board apparatus. As a result, for example, it is possible to reduce the occurrence of open defects due to the above insufficient number of trapped conductive particles. Further, for example, since the fluctuation of the number of trapped conductive particles can be reduced, a stable electric resistance value can be obtained.

  In the present embodiment, the value of both positioning accuracy is calculated by a manufacturing method described later. However, in the present invention, the method of calculating the value of both positioning accuracy is not particularly limited. The positioning accuracy values include, for example, manufacturing tolerances of the first board and the second board, and mounting positions of connection equipment for electrically connecting the first connection terminal and the second connection terminal. It may be calculated from a tolerance, such as a dimensional tolerance accompanying a change in shape of the first substrate and the second substrate due to an environmental change.

  The calculation of the values of both positioning accuracy is not limited to the time of manufacturing the circuit board device. For example, the material for forming the first substrate and the second substrate in the manufactured circuit board device, the direction in which the two substrates are cut out from the raw material, the thermal history during manufacture assumed from the material for forming the connection terminals, or The value of the positioning accuracy can be calculated from the temperature / humidity conditions where the circuit board device is stored.

  In the circuit board device of the present invention, for each of the connection terminals, as described above, a polygon having an angle set in accordance with the position shift direction between the connection terminals in the circuit board device is selected. Thereby, the fluctuation | variation of the overlap area between connection terminals by position shift can be reduced. Therefore, unlike the circuit board device described in Patent Document 2 described above, for example, a positioning terminal is not necessarily provided for the purpose of improving positioning accuracy. Therefore, the circuit board device of the present invention has a simple configuration. Further, since it is not always necessary to provide the positioning terminals, for example, the degree of freedom of the wiring layout on the substrate is high.

  In the circuit board device of the present embodiment, as described above, the first printed wiring board 101 is a rigid printed wiring board having FR4 as a base material. The second printed wiring board 102 is a flexible printed wiring board based on polyimide. However, the present invention is not limited to this example, and the first substrate and the second substrate can be used by arbitrarily combining, for example, a rigid printed wiring board and a flexible printed wiring board. Further, the formation material of the rigid printed wiring board is not limited to FR4, and examples thereof include FR1, FR2, FR3, CEM3, Teflon (registered trademark), alumina, ceramics, and glass. Further, the material for forming the flexible printed circuit board is not limited to polyimide, and examples thereof include polyethylene terephthalate (PET) and polyethylene naphthalate (PEN).

  In the present embodiment, the above-described anisotropic conductive film is used as the anisotropic conductive material, but the present invention is not limited to this example. An anisotropic conductive material exhibits electrical anisotropy that exhibits conductivity in the thickness direction in the crimped portion and exhibits insulation in the surface direction by thermocompression bonding in a manufacturing method described later. Anything is acceptable. The binder in the anisotropic conductive material is not limited to the aforementioned polyimide, and examples thereof include acrylic, epoxy, and silicone. The conductive particles (metal particles) in the anisotropic conductive material are not limited to the aforementioned Ni, and examples thereof include Ni / Au plated resin particles. The shape is not limited to a film shape, and may be a paste shape (an anisotropic conductive paste, ACP: Anisotropic Conductive Paste). The anisotropic conductive material can be arbitrarily selected according to the intended electrical characteristics. In order to ensure electrical connection between the two connection terminals, it is necessary that one or more conductive particles remain in the gap between the pair of connection terminals. The remaining number of the conductive particles is preferably 5 to 10. This number of remaining conductive particles is called the number of captured conductive particles. The anisotropic conductive material defines a minimum overlap area so that the number of trapped conductive particles is not less than one. In addition, an overlap area means the area of the part which the connection terminals electrically connected overlap, for example. Further, the above description does not limit the present invention.

  The manufacturing method of the circuit board device of the present invention is not particularly limited, but is preferably manufactured by the manufacturing method of the present invention. Hereinafter, an example of a method for manufacturing the circuit board device of the present embodiment will be described with reference to FIG. The manufacturing method of the circuit board device of this embodiment includes a board preparation process and an electrical connection process.

[Board preparation process]
In the substrate preparation step, the first printed circuit board 101 having a plurality of first connection terminals 103 arranged on one surface and the plurality of second connection terminals 104 arranged on one surface are provided. A second printed wiring board 103 is prepared. The substrate preparation step includes a first connection terminal arrangement step and a second connection terminal arrangement step.

[First connection terminal arrangement step]
First, the first connection terminal arrangement step will be described. A first printed wiring board 101 which is a rigid printed wiring board using FR4 as a base material is prepared. The first connection terminals 103 are arranged on the surface of the first printed wiring board 101 facing the second printed wiring board 102. The planar shape and arrangement of the first connection terminals 103 are as described above. The angle θ1 of the angle a at each first connection terminal 103 is a cosine angle that is an acute angle formed by the straight line in the misalignment direction ds and the straight line in the arrangement direction x, which is calculated from the positioning accuracy values dx and dy. It sets so that it may become an angle which satisfy | fills the relationship of said Formula (3) with respect to angle (PHI).

[Second connection terminal arrangement step]
Next, the second connection terminal arrangement step will be described. A second printed wiring board 102, which is a flexible printed wiring board based on polyimide, is prepared. The second connection terminals 104 are arranged on the surface of the second printed wiring board 102 facing the first printed wiring board 101. The planar shape and arrangement of each second connection terminal 104 are as described above.

  For example, the values dx and dy of the positioning accuracy are set to the manufacturing tolerances of the first printed wiring board 101 and the second printed wiring board 102, and the first connection terminal 103 and the second connection terminal 104 are electrically connected. It is calculated from tolerances such as a mounting position tolerance of connection equipment to be connected and a dimensional tolerance accompanying a shape change of the first printed wiring board 101 and the second printed wiring board 102 due to environmental changes. In this manner, a substrate used in the circuit board device of this embodiment is manufactured. In addition, in the board | substrate preparation process in the manufacturing method of the circuit board apparatus of this embodiment, the board | substrate is produced by performing these processes, However, This invention is not limited to this example. A previously prepared substrate may be prepared.

[Electrical connection process]
Next, as shown in FIG. 3A, an anisotropic conductive film 105 is sandwiched between the first connection terminal 103 and the second connection terminal 104 prepared in the substrate preparation step. In this state, positioning is performed with the above-described values of both positioning accuracy using a positioning facility (not shown). Next, as shown in FIG. 3B, the first printed wiring board 101 and the second printed wiring board 102 are heated at 190 ° C. and pressurized at 5 MPa, for example, using the heater tool 106. Thus, the anisotropic conductive film 105 is disposed between the connection terminals. Thereby, the first printed wiring board 101 and the second printed wiring board 102 are electrically connected (electrical connection step). In this way, as shown in FIG. 3C, the circuit board device 100 of the present embodiment can be manufactured. However, the method for manufacturing the circuit board device of the present embodiment is not limited to this example.

  In the method for manufacturing a circuit board device according to the present embodiment, for example, as in the circuit board device described in Patent Document 2, it is not always necessary to provide a positioning terminal for the purpose of improving positioning accuracy. The process can be simplified.

(Embodiment 2)
FIG. 4 shows a configuration of an example of the circuit board device of the present embodiment. FIG. 4A is a plan view of the circuit board device of the present embodiment. FIG. 4B is an enlarged plan view of a connection portion of a region 210 surrounded by a two-dot chain line of the circuit board device shown in FIG. FIG. 4C is a diagram showing a misalignment direction in the circuit board device of the present embodiment. As shown in the figure, in this circuit board device 200, the values dx and dy of both positioning accuracy are the same as those in the first embodiment. Each first connection terminal 203 is a pentagon in which the angle θ1 of the angle a is the same angle (126.870 °) as in the first embodiment. In each of the pentagons, the corners c and d that are not adjacent to the corner a are right angles. Its width L3 is 0.339 mm. Its length H3 is 0.338 mm. The area C is 0.100 mm ² . The equivalent pitch Px in the arrangement direction x is 0.25 mm. The planar shape of each second connection terminal 204 is the same as that of the first connection terminal 203, and the position of each second connection terminal 204 corresponds to each first connection terminal 203 on a one-to-one basis. Is arranged. Other configurations are the same as those of the circuit board device 100 described above.

In the circuit board device according to the present embodiment, the overlap area C ′ between the first connection terminal 203 and the second connection terminal 204 due to the displacement between the connection terminals is 0.060 mm ² . Since it is more than the minimum overlap area (0.050 mm < ² >) of the anisotropic conductive film 105, the open defect resulting from the above-mentioned insufficient number of conductive particle capture does not occur. In addition, the same effects as those of the first embodiment can be obtained.

  The circuit board device of the present embodiment is manufactured by the same method as that of the first embodiment, for example, except that each first connection terminal 203 and each second connection terminal 204 has the above-described pentagonal shape. can do. However, the method for manufacturing the circuit board device of the present embodiment is not limited to this example.

  In Embodiments 1 and 2, the arrangement of the first connection terminals and the second connection terminals is a staggered arrangement, but the present invention is not limited to this example. The arrangement of the first connection terminals and the second connection terminals may be, for example, a one-row arrangement as shown in FIGS. 5 (a) and 5 (b). In the case of the staggered arrangement, the pitch between the first connection terminals and the second connection terminals in the case of the one-row arrangement (Px1 in FIG. 5A and FIG. 5B). Px2) is preferable because it can be arranged at a narrower pitch and can cope with a narrower pitch.

  Moreover, in Embodiment 1 and Embodiment 2, although the planar shape of the said 1st connection terminal and the said 2nd connection terminal is a hexagon or a pentagon, this invention is not limited to this example. The planar shape of the first connection terminal and the second connection terminal has an angle that satisfies the relationship of the expression (1) in the present invention, and the angle is oriented in a direction orthogonal to the arrangement direction. Any polygon may be used as long as it is arranged. For example, as shown in FIG. 5C, each of the first connection terminals 213 and each of the second connection terminals 214 has an angle a whose plane shape is an angle θ1, and the angle a is directed in the direction y. It may be a rhombus. Even in such a case, the overlap area D ′ of the first connection terminal 213 and the second connection terminal 214 due to misalignment with respect to the area D of each of the first connection terminals 213 and each of the second connection terminals 214 Variations can be reduced. In the present invention, when the area of each connection terminal and the positioning accuracy values are constant, the planar shape of the connection terminal is a polygon having five or more corners (for example, a hexagon or a pentagon). ) Is preferred compared to a triangle or square. This is because the former can reduce the width or length in the planar shape and the corresponding pitch (in FIG. 5C, the width L4 or the length H4 and Px3 in FIG. 5C) and can cope with a narrower pitch than the latter. is there. However, this invention is not restrict | limited at all by this.

  Moreover, in Embodiment 1 and Embodiment 2, although the length of two sides which form the angle a is the same, this invention is not limited to this example. The two sides may have different lengths.

(Embodiment 3)
FIG. 6 shows an example of the configuration of the circuit board device of the present embodiment. FIG. 6A is a plan view of the circuit board device of the present embodiment. FIG. 6B is an enlarged plan view of a connection portion of a region 310 surrounded by a two-dot chain line of the circuit board device shown in FIG. FIG. 6C is a diagram showing a misalignment direction in the circuit board device of the present embodiment. As illustrated, in this circuit board device 300, the positioning accuracy value dx1 of the first connection terminals 303 in the arrangement direction x is 0.087 mm. In addition, the positioning accuracy value dy1 in the direction y perpendicular to the arrangement direction x of the first connection terminals 303 is 0.050 mm. From the positioning accuracy value dx1 in the direction x and the positioning accuracy value dy1 in the direction y, as shown in FIG. 6C, a positional deviation direction ds1 is calculated. An angle Φ1 of a cosine angle that is an acute angle formed by the straight line in the positional deviation direction ds1 and the straight line in the direction x is 30 °. With respect to this angle Φ1, the angle θ3 of the hexagonal angle e which is the planar shape of the first connection terminal 303 is set so as to satisfy the following formula (4). The angle θ3 is 120 °. The “angle θ3” in the present embodiment corresponds to the “angle θ” in the present invention. The “angle Φ1” in the present embodiment corresponds to the “angle Φ” in the present invention.

θ3 = 180 ° −2 × Φ1 (4)

The planar shape of each first connection terminal 303 is a regular hexagon. In each of the regular hexagons, the length La of one side is 0.196 mm. The area E is 0.100 mm ² . The equivalent pitch Px in the arrangement direction x is 0.245 mm. Other configurations are the same as those of the circuit board device 100 described above.

In the circuit board device according to the present embodiment, the overlap area E ′ between the first connection terminal 303 and the second connection terminal 304 due to the displacement between the connection terminals is 0.066 mm ² . Since it is more than the minimum overlap area (0.050 mm < ² >) of the anisotropic conductive film 105, the open defect resulting from the above-mentioned insufficient number of conductive particle capture does not occur. In addition, the same effects as those of the first embodiment can be obtained.

  The circuit board device of the present embodiment is, for example, the same method as that of the first embodiment, except that each first connection terminal 303 and each second connection terminal 304 has a regular hexagonal shape as described above. Can be manufactured. However, the method for manufacturing the circuit board device of the present embodiment is not limited to this example.

  In the first to third embodiments, the planar shapes of the first connection terminals and the second connection terminals are defined as one type, respectively, but the present invention is not limited to this example. As long as each said 1st connection terminal and each said 2nd connection terminal are the polygons prescribed | regulated by this invention, you may use combining the polygon of a different planar shape.

  As described above, the circuit board device of the present invention can reduce the variation in the overlap area between the connection terminals due to the displacement. Accordingly, the circuit board device according to the present invention holds, for example, wiring boards that are mounted on an electronic device in the field of electrical / communication and that are provided with printed wiring such as flexible printed wiring boards and rigid printed wiring boards. The circuit board device can be used. However, its use is not limited and can be applied to a wide range of fields. Examples of the electronic device include a mobile phone device, a PDA (Personal Digital Assistant) terminal, and a personal computer terminal.

100, 200, 300 Circuit board device 101 First printed wiring board (first board)
102 Second printed wiring board (second board)
103, 203, 213, 303 First connection terminal 103 ′ First connection terminals 104, 204, 214, 304 in the circuit board device used for comparison Second connection terminal 104 ′ Second connection terminal 104 ′ in the circuit board device used for comparison 2 connection terminals 105 Anisotropic conductive film (anisotropic conductive material)
106 Heater tools 110, 210, 310 Area 110 'surrounded by two-dot chain line Area 700' surrounded by two-dot chain line 700 Electrical connection structure of membrane switch and LCD described in Non-Patent Document 1 (circuit board device)
701 Glass substrate 702 PET film 703, 704 Counter electrode 705 Anisotropic conductive material (ACF or ACP)
706 Binder 707 Conductive particle 708 LCD
800 Circuit board device 801 described in Patent Document 2 First board 802 Second board 803, 804 Connection terminal 805a, 805b, 806a, 806b Positioning terminal 807 Thermoplastic bonding member 808 ACF
809 Local heater 810 Thermocompression bonding tool

Claims (20)

A first substrate and a second substrate facing each other;
The first substrate has a plurality of first connection terminals arranged on a surface facing the second substrate,
The second substrate has a plurality of second connection terminals arranged on a surface facing the first substrate,
Each of the first connection terminals is arranged such that a planar shape thereof is a polygon and at least one corner of the polygon is oriented in a direction y orthogonal to the arrangement direction x;
Each of the second connection terminals has the same planar shape as the first connection terminal, and the position of each of the second connection terminals has a one-to-one correspondence with each of the first connection terminals. Are arranged as
By arranging an anisotropic conductive material between the first connection terminal and the second connection terminal, the first substrate and the second substrate are electrically connected,
A cosine which is an acute angle formed by a straight line in a misalignment direction and a straight line in the arrangement direction x, which is calculated from a positioning accuracy value in the arrangement direction x and a positioning accuracy value in a direction y orthogonal to the arrangement direction x. The circuit board device according to claim 1, wherein the angle θ of the angle directed in the direction y satisfies the relationship of the following formula (1) with respect to the angle Φ.

θ = 180 ° -2 × Φ (1)
2. The circuit board device according to claim 1, wherein the array is a staggered array. The polygon is a hexagon;
3. The circuit board device according to claim 1, wherein an angle of an angle of the hexagon facing the direction y is equal to an angle of an angle located at two angles with respect to the angle. The polygon is a hexagon;
The angle Φ is 30 °;
The circuit board device according to claim 1, wherein the angle θ is 120 °. The polygon is a pentagon;
There is one angle in the direction y,
3. The circuit board device according to claim 1, wherein an angle between two corners that are not adjacent to the corner in the direction y is a right angle. The value of both positioning accuracy is the manufacturing tolerance of the first board and the second board, the mounting position tolerance of the connection equipment that electrically connects the first connection terminal and the second connection terminal, And calculating from at least one tolerance selected from the group consisting of dimensional tolerances associated with changes in the shape of the first substrate and the second substrate due to environmental changes. The circuit board device according to one item. It is used for the circuit board device according to any one of claims 1 to 6,
It has a plurality of connection terminals on one side,
Each of the connection terminals is arranged such that the planar shape thereof is a polygon and at least one corner of the polygon faces a direction y orthogonal to the arrangement direction x.
A cosine which is an acute angle formed by a straight line in a misalignment direction and a straight line in the arrangement direction x, which is calculated from a positioning accuracy value in the arrangement direction x and a positioning accuracy value in a direction y orthogonal to the arrangement direction x. A substrate in which an angle θ of an angle directed in the direction y with respect to an angle Φ of the angle satisfies the relationship of the formula (1). The substrate according to claim 7, wherein the array is a staggered array. The polygon is a hexagon;
9. The substrate according to claim 7, wherein an angle of an angle of the hexagon facing the direction y is equal to an angle of an angle located at two angles with respect to the angle. The polygon is a hexagon;
The angle Φ is 30 °;
The substrate according to claim 7, wherein the angle θ is 120 °. The polygon is a pentagon;
There is one angle in the direction y,
9. The substrate according to claim 7, wherein an angle between two corners not adjacent to the corner in the direction y is a right angle. The value of both positioning accuracy is the manufacturing tolerance, the mounting position tolerance of the connection equipment that electrically connects the connection terminal to another connection terminal in the same shape and the same shape as the connection terminal, and the shape change due to the environmental change. The substrate according to claim 7, wherein the substrate is calculated from at least one tolerance selected from the group consisting of accompanying dimensional tolerances. A substrate preparation step of preparing a first substrate having a plurality of first connection terminals arranged on one surface and a second substrate having a plurality of second connection terminals arranged on one surface; ,
An anisotropic conductive material is sandwiched between the first connection terminal and the second connection terminal, and the anisotropic is applied between the first connection terminal and the second connection terminal by heating and pressing. An electrical connection step of electrically connecting the first substrate and the second substrate by disposing a conductive material;
Each of the first connection terminals is arranged such that a planar shape thereof is a polygon and at least one corner of the polygon is oriented in a direction y orthogonal to the arrangement direction x;
Each of the second connection terminals has the same planar shape as the first connection terminal, and the position of each of the second connection terminals has a one-to-one correspondence with each of the first connection terminals. Are arranged as
A cosine which is an acute angle formed by a straight line in a misalignment direction and a straight line in the arrangement direction x, which is calculated from a positioning accuracy value in the arrangement direction x and a positioning accuracy value in a direction y orthogonal to the arrangement direction x. A method of manufacturing a circuit board device, wherein an angle θ of an angle directed in the direction y with respect to an angle Φ of the angle satisfies a relationship of the following formula (2).

θ = 180 ° -2 × Φ (2)
A first connecting terminal arranging step of arranging the first connecting terminals on a surface of the first substrate facing the second substrate of the first substrate;
A second connection terminal arrangement step of arranging the second connection terminals on a surface of the second substrate facing the first substrate;
In the first connecting terminal arrangement step,
A straight line in a misalignment direction, wherein an angle θ of at least one corner of the polygon is calculated from a positioning accuracy value in the arrangement direction x and a positioning accuracy value in a direction y orthogonal to the arrangement direction x; Set so as to satisfy the relationship of the above formula (2) with respect to the angle Φ of the cosine angle which is an acute angle with the straight line in the arrangement direction x, and
Arranging the first connection terminals of the plurality of polygons so that at least one corner of the polygon faces a direction y orthogonal to the arrangement direction x;
In the second connection terminal arrangement step,
Each of the second connection terminals has a planar shape that is the same as the first connection terminal, and
14. The method of manufacturing a circuit board device according to claim 13, wherein the positions of the respective second connection terminals are arranged so as to correspond to the respective first connection terminals on a one-to-one basis. The method for manufacturing a circuit board device according to claim 13 or 14, wherein, in the first connection terminal arrangement step, the arrangement is made in a staggered arrangement. In the first connecting terminal arrangement step, the polygon is a hexagon, and an angle of a corner of the hexagon that is oriented in the direction y and an angle of the corner that is located at two angles to the corner The method of manufacturing a circuit board device according to claim 13, wherein the circuit board device is made equal to each other. The said 1st connection terminal arrangement | sequence process WHEREIN: The said polygon is made into a hexagon, the said angle (PHI) is 30 degrees, and the said angle (theta) is 120 degrees, It is any one of Claim 13-16 characterized by the above-mentioned. A method for manufacturing a circuit board device according to claim 1. In the first connecting terminal arrangement step, the polygon is a pentagon having one angle in the direction y, and the angle between two angles not adjacent to the angle in the direction y is a right angle. The method for manufacturing a circuit board device according to claim 13, wherein the circuit board device is manufactured as described above. The value of both positioning accuracy is the manufacturing tolerance of the first board and the second board, the mounting position tolerance of the connection equipment that electrically connects the first connection terminal and the second connection terminal, And calculating from at least one tolerance selected from the group consisting of dimensional tolerances accompanying a change in shape of the first substrate and the second substrate due to environmental changes. The manufacturing method of the circuit board apparatus as described in an item. An electronic circuit comprising the circuit board device according to any one of claims 1 to 6 or the circuit board device manufactured by the manufacturing method according to any one of claims 13 to 19. machine.

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