Method for manufacturing connection structure, connection structure, film structure, and method for manufacturing film structure

Abstract

A method for manufacturing a connection structure that can mount an electronic component having multiple terminal rows on its mounting surface using existing equipment, a connection structure, a film structure, and a method for manufacturing the film structure are provided. [Solution] The method includes an attachment step of attaching connection films 22, 23, each having a unit area of ​​a predetermined length 21L in the longitudinal direction of the substrate 21 and a predetermined width 21W in the width direction of the substrate 21, from a film structure comprising a tape-like substrate 21 and a connection film formed on the substrate 21, to a first electronic component or a second electronic component having a plurality of terminal rows, and a connection step of connecting the terminals of the first electronic component and the terminals of the second electronic component via the connection films 22, 23, wherein the film structure has non-attached portions in the unit area where the connection film is not attached other than at locations corresponding to the plurality of terminal rows.

Description

[Technical Field]

[0001] The present technology relates to a method for manufacturing a connection structure in which electronic components are connected, a connection structure, a film structure, and a method for manufacturing a film structure. [Background technology]

[0002] Conventionally, ACF (Anisotropic Conductive Film), NCF (Non-Conductive Film), etc. have been known as connection films for connecting various electronic components, and camera modules and the like have been mounted using connection films (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2015-130426 Summary of the Invention [Problem to be solved by the invention]

[0004] In recent years, electronic components have become known that have a recess in the center of their mounting surface. For example, in camera modules, the center of a ceramic substrate is hollowed out to accommodate an image sensor, and a recess is formed in the center of the mounting surface, with a terminal row formed around the periphery of the mounting surface. Electronic components with multiple terminal rows on their mounting surface and electronic components whose mounting surface consists of multiple protrusions and have terminal rows on the protrusions are also considered to be classified as components with a recess.

[0005] When mounting electronic components with multiple terminal rows on their mounting surfaces using a connection film, significant improvements to the mounting equipment are required. For example, when attaching a connection film to each of the multiple terminal rows on the mounting surface, the connection film must be attached multiple times. Furthermore, when mounting an electronic component with a recess in the center of the mounting surface by attaching a connection film to the entire mounting surface, there is a concern that gas may fill the recess, reducing the reliability of the connection.

[0006] The present technology has been proposed in consideration of the current situation, and provides a method for manufacturing a connection structure that can mount electronic components having multiple terminal rows on the mounting surface using existing equipment, as well as a connection structure, a film structure, and a method for manufacturing a film structure. [Means for solving the problem]

[0007] The method for manufacturing a connection structure according to the present technology includes an attachment step of attaching a connection film having a unit area of ​​a predetermined length in the longitudinal direction of the base and a predetermined width in the width direction of the base from a film structure including a tape-like base material and a connection film formed on the base material to a first electronic component or a second electronic component having a plurality of terminal rows, and a connection step of connecting terminals of the first electronic component and terminals of the second electronic component via the connection film, wherein the film structure has non-attached portions in the unit area where the connection film is not attached other than at locations corresponding to the plurality of terminal rows.

[0008] The connection structure according to the present technology includes a first electronic component having a plurality of terminal rows, a second electronic component, and a cured film formed by curing a connection film having voids in a unit area of ​​a predetermined length and a predetermined width in a planar view between the first electronic component and the second electronic component, other than at locations corresponding to the plurality of terminal rows, and the terminals of the first electronic component and the terminals of the second electronic component are connected to each other.

[0009] The film structure according to the present technology comprises a tape-shaped substrate and a connecting film formed on the substrate, and has a unit area of ​​a predetermined length in the longitudinal direction of the substrate and a predetermined width in the width direction of the substrate in a plan view, and has a non-attached portion extending from the periphery of the unit area toward the center of the unit area.

[0010] The method for manufacturing a film structure according to the present technology includes a processing step of processing a raw film sheet having a tape-like substrate and a connecting film formed on the substrate, and in the processing step, a film structure is formed which has a unit area having a predetermined length in the longitudinal direction of the substrate and a predetermined width in the width direction of the substrate in a planar view, and which has a non-attached portion extending from the periphery of the unit area toward the center of the unit area. [Effects of the Invention]

[0011] According to this technology, the connection film has non-attached portions to which the connection film is not attached other than at locations corresponding to multiple terminal rows in a unit area, so that electronic components having multiple terminal rows can be mounted on the mounting surface using existing mounting equipment. [Brief explanation of the drawings]

[0012] [Figure 1] FIG. 1 is a plan view showing the mounting surface of the camera module. [Figure 2] FIG. 2 is a cross-sectional view taken along line II-II shown in FIG. [Figure 3] FIG. 3 is a plan view showing a unit area of ​​the film structure. [Figure 4] FIG. 4 is a cross-sectional view taken along line IV-IV shown in FIG. [Figure 5] FIG. 5 is a cross-sectional view showing a bonding step of bonding a connecting film to a camera module. [Figure 6] FIG. 6 is a cross-sectional view showing a state in which the substrate has been peeled off from the connecting film in the bonding step. [Figure 7] FIG. 7 is a cross-sectional view showing a mounting process for mounting a flexible substrate on a camera module. [Figure 8] FIG. 8 is a cross-sectional view showing a connecting step for connecting the terminals of the camera module and the terminals of the flexible substrate via the connecting film. [Figure 9] FIG. 9 is a cross-sectional view showing a connection structure on which a camera module is mounted. [Figure 10] FIG. 10 is a cross-sectional view showing an example of the configuration of a connection structure on which a camera module is mounted. [Figure 11] FIG. 11 is a perspective view showing a film roll. [Figure 12] FIG. 12 is a plan view showing a film structure of the first modification. [Figure 13] FIG. 13 is a plan view showing a film structure of the second modification. [Figure 14] FIG. 14 is a plan view showing a film structure of the third modification. [Figure 15] FIG. 15 is a plan view showing a film structure of the fourth modification. [Figure 16] FIG. 16 is a plan view showing the mounting surface of another example of the camera module. [Figure 17] FIG. 17 is a plan view showing a first example of a film structure corresponding to the mounting surface shown in FIG. [Figure 18] FIG. 18 is a plan view showing a second example of a film structure corresponding to the mounting surface shown in FIG. [Figure 19] FIG. 19 is a plan view showing a third example of a film structure corresponding to the mounting surface shown in FIG. [Figure 20] FIG. 20 is a plan view showing an example of a mounting surface of a camera module according to another embodiment. [Figure 21] FIG. 21 is a plan view showing an example of a connection film corresponding to the mounting surface of the camera module shown in FIG. [Figure 22] FIG. 22 is a perspective view showing an example of a tape-shaped film structure around which the connecting film shown in FIG. 21 is wound. [Figure 23] FIG. 23 is a cross-sectional view in the width direction including the non-attached portion of the film structure. DETAILED DESCRIPTION OF THE INVENTION

[0013] Hereinafter, embodiments of the present invention will be described in detail in the following order with reference to the drawings. 1.Method for manufacturing a connection structure 2. Connection structure 3.Film structure 4.Method for manufacturing film structure 5. Variations 6. Working Example

[0014] <1. Method for manufacturing connection structure> The method for manufacturing a connection structure according to this embodiment includes a film structure including a tape-like substrate and a connection film formed on the substrate. The connection film has a unit area with a predetermined length in the longitudinal direction of the substrate and a predetermined width in the width direction of the substrate. The connection film is attached to a first electronic component or a second electronic component having multiple terminal rows. The connection film connects the terminals of the first electronic component and the terminals of the second electronic component via the connection film. The film structure has non-attached portions in the unit area where the connection film is not attached, except for the locations corresponding to the multiple terminal rows. This allows electronic components having multiple terminal rows to be mounted on a mounting surface using existing mounting equipment. Furthermore, the attachment step allows the connection film to be attached all at once, without having to be attached multiple times to correspond to the multiple terminal rows.

[0015] Here, the term "unit area" refers to a rectangular area having a predetermined length in the longitudinal direction of the substrate, and the term "non-attached portion" refers to an area in the unit area where the connection film is not attached to the electronic component, such as a gap where no connection film is present or a connection film that is not attached due to cutting.

[0016] Examples of the first electronic component include those whose mounting surface is composed of multiple protrusions and has a terminal row on the protrusions, those whose flat mounting surface has multiple terminal rows, and those whose mounting surface has a recess in the center and a terminal row formed on the periphery of the mounting surface. A first electronic component having a recess in the center of the mounting surface may have, for example, a rectangular mounting surface with terminal rows on two opposing sides of the recess's periphery, two adjacent sides (L-shaped), or three sides of the recess's periphery (U-shaped, C-shaped). The terminal row may also be located around the entire periphery. The periphery of the recess and the terminal row may be configured only parallel or perpendicular, but this is not limited to this and can be adjusted appropriately depending on the target object. Therefore, the shape of the unit area of ​​the connecting film can also be adjusted appropriately accordingly.

[0017] The outer shape of the mounting surface need not be rectangular, but may be, for example, a curved shape, a circle, a polygon, or the like. The outer shape of the mounting surface may be formed from edges as described above, or may have a shape with the interior removed (punched out). The shape of the mounting component having the mounting surface may or may not be the same as the mounting surface. This may be the case for either the first electronic component or the second electronic component, or both (not shown).

[0018] When the first electronic component has a recess in the center of the mounting surface, the film structure preferably has a non-attached portion extending from the periphery of the unit area toward the center of the unit area, which prevents the recess from filling with gas and reducing the reliability of the connection.

[0019] When the unit area of ​​the film structure is rectangular, it is preferable that the non-attached portion is formed from the center of at least one side of the unit area toward the center of the unit area, which allows a first electronic component having a mounting surface with a terminal row formed on three sides (U-shaped) of the periphery of the recess to be mounted.

[0020] Furthermore, when the unit area of ​​the film structure is rectangular, it is preferable that the non-attached portion is formed in the unit area from the center in the width direction of the base material to the length direction of the base material, thereby making it possible to mount a first electronic component having a mounting surface with terminal rows formed on two opposing sides of the periphery of the recess.

[0021] Furthermore, in the unit area of ​​the film structure, the connection film may be linearly processed to form a polygonal shape, such as a hexagon, octagon, or dodecagon, or a U-shape, or a curved U-shape, C-shape, or cylindrical attachment portion. The attachment portion of the connection film may also have a shape that combines straight and curved lines. The polygonal shape may be a regular polygon. The corners of these shapes may also be chamfered. The attachment portion of the connection film may also have a shape that is partially missing. For example, the corners of a rectangle may be missing, and the attachment portion of the connection film may have a cross or similar shape. For example, if the unit area of ​​the film structure is rectangular, the corners of the rectangular connection film may be chamfered in a straight line to form a non-attachment portion, and the attachment portion may be octagonal. An octagon can also be formed by linearly chamfering each corner of a square or rectangular connection film, and a cross shape can also be formed by missing the corners of a square or rectangular connection film. This allows the connection film to be mounted in an octagonal or cross shape. The chamfering and cutting are not limited to straight lines, but may be curved, or a combination of straight and curved lines. The octagonal and cross-shaped connection films are merely examples, and only a portion of the film may be chamfered or cut. The connection film may also have a shape with a portion removed (punched). Similarly, the shape of the connection film is not limited to straight lines, but may be curved, or a combination of straight and curved lines. In this case, the film structure may be such that only the connection film is removed, or the connection film and the substrate are removed. This prevents resin from overflowing, particularly at the corners of the mounting surface, and reaching a large area on the side of the mounted component when the connection film is used for connection. Furthermore, when the component is assembled with other components, unnecessary resin contact with the other components is more easily avoided, contributing to the prevention of contamination. The more precise and compact the component, the more preferable the chamfering and cutting (punched) shape.

[0022] In the film structure, it is preferable that at least a portion of the attachment portion in each unit area has the same shape as the mounting surface of the first electronic component or the second electronic component. That is, the attachment portion of the connection film may be, for example, rectangular, curved, circular, or polygonal, depending on the shape of the mounting surface. These shapes may also be partially missing, such as U-shaped, C-shaped, or the like. The attachment portion of the connection film may also have a hollowed-out shape, where a portion of the surface is removed. By matching the shape of the attachment portion of the connection film to the contour of the mounting surface, it is possible to prevent a portion of the connection film from excessively protruding from the mounting surface. This facilitates handling of the electronic components to be mounted, improves workability, prevents interference with previous and subsequent processes, and ultimately reduces overall manufacturing costs. For example, in the process of attaching the connection film to a substrate (temporary attachment), the similar contours of the substrate and the connection film are expected to improve workability.

[0023] Furthermore, in the film structure, the size of the outer periphery of the attachment portion in a unit area may be smaller, the same as, or larger than the size of the outer periphery of the mounting surface of the first electronic component or the second electronic component. Considering the prevention of excessive protrusion of the adhesive film, the lower limit of the size of the outer periphery of the attachment portion relative to the size of the outer periphery of the mounting surface is preferably 50% or more, more preferably 80% or more. Furthermore, the upper limit of the size of the outer periphery of the mounting surface is preferably 110% or less, more preferably 105% or less, and even more preferably 100% or less, because if the size is too small, it is desirable to have a margin for stable attachment when performing continuous mounting. These limits require that the connection film be present so as to adequately cover the terminals on the mounting surface, and can be adjusted appropriately depending on the width and shape of the mounting surface. The size of the attachment portion may be adjusted taking into account the effective connection area and the influence of protrusion. It is preferable that the shapes of the outer edge of the attachment portion and the mounting surface of the first electronic component or the second electronic component are the same or similar, but even if there are some differences, this does not exclude the scope of the present technology.

[0024] Furthermore, the film structure preferably has a non-adhesive portion in the center of each unit region. This corresponds to the connection film having an adhesive portion in the shape of a U-shape, a C-shape, or the like described above. The non-adhesive portion may also have a hollowed-out shape, with a portion of the surface removed. That is, in the film structure, the adhesive portion has an outer peripheral edge and an inner peripheral edge in each unit region. The adhesive portion of the connection film is required to have a sufficient effective connection area between the outer peripheral edge and the inner peripheral edge. This prevents unnecessary and excessive protrusion of the connection film and prevents gas from filling when an electronic component having a recess on the mounting surface is mounted. The non-adhesive portion may also be a slit or hole. Furthermore, shapes such as a U-shape, a C-shape, or a C-shape do not necessarily need to be connected. As such, the film structure may be composed of sides, and therefore may have a hollowed-out shape with all of the sides forming the outer shape connected. The film structure may also be formed by providing adhesive portions on a substrate at intervals corresponding to the sides constituting these shapes. If the processes of temporarily attaching and connecting the connecting film are performed in one go, workability will be improved, and if they are performed edge by edge, the required equipment modifications will be minimal, reducing implementation costs. Furthermore, since the connecting film (attachment portion) on such an edge is placed on the substrate, only one film roll will be required to be pulled out, and it is expected that relatively little modification of existing manufacturing equipment will be required. The same effect can be expected even if the edges that form the outer shape are all connected and the inside is cut out. Appropriate selection can be made depending on conditions such as constraints on equipment modifications for the temporary attachment and crimping of the connecting film.

[0025] The first electronic component and the second electronic component are not particularly limited and can be appropriately selected depending on the purpose. Examples of the first electronic component include a ceramic substrate, a rigid substrate, a flexible substrate (FPC: Flexible Printed Circuits), a glass substrate, a plastic substrate, a resin multilayer substrate, an IC (Integrated Circuit) module, an IC chip, etc. Examples of the second electronic component include a ceramic substrate, a rigid substrate, a flexible substrate (FPC: Flexible Printed Circuits), a glass substrate, a plastic substrate, a resin multilayer substrate, etc.

[0026] In functional modules such as camera modules, ceramic substrates are sometimes used due to their excellent electrical and thermal insulation properties. Ceramic substrates are also used for miniaturization (for example, 1 cm 2 It has advantages such as excellent dimensional stability at high temperatures (see below).

[0027] The connection film is not particularly limited, and examples thereof include a film-shaped anisotropic conductive film (ACF: Anisotropic Conductive Film) and a film-shaped adhesive film (NCF: Non-Conductive Film). The curing type of the connection film is also not particularly limited, and examples thereof include a thermosetting type, a photosetting type, and a photothermal and combined photosetting and thermal setting type. The connection film may also be a hot-melt type using a thermoplastic resin. The connection film according to the present technology is provided on a substrate (substrate film) and is separable from the release film. This differs from a connection film in which an adhesive or a curable resin is used integrally with the substrate (used without being separated). Therefore, advanced processing technology for the connection film is required.

[0028] This technology can be used in manufacturing methods for any electronic device that uses electrical connections, such as semiconductor devices (including driver ICs as well as optical elements, thermoelectric conversion elements, photoelectric conversion elements, and other devices that use semiconductors), display devices (monitors, televisions, head-mounted displays, etc.), mobile devices (tablet devices, smartphones, wearable devices, etc.), game consoles, audio equipment, imaging devices (devices that use image sensors such as camera modules), electrical packaging for vehicles (mobile devices), medical equipment, sensor devices (touch sensors, fingerprint authentication, iris authentication, etc.), and home appliances.

[0029] Hereinafter, a specific example will be described using a method for manufacturing a connection structure for mounting a camera module. The specific example of the method for manufacturing the connection structure includes an attachment step of attaching a connection film to the camera module, a mounting step of mounting a flexible substrate on the camera module, and a connection step of connecting terminals of the camera module and terminals of the flexible substrate via the connection film.

[0030] [Camera module] Fig. 1 is a plan view showing the mounting surface of a camera module, and Fig. 2 is a cross-sectional view taken along line II-II in Fig. 1. As shown in Figs. 1 and 2, camera module 10 includes ceramic substrate 11 having a recess (cavity) on its rectangular mounting surface, first terminal row 12 and second terminal row 13 formed on two opposing sides of the periphery of the recess on the rectangular mounting surface, and image sensor 14 housed in the recess. Furthermore, in the cross section taken along line II-II, camera module 10 has a mounting surface of predetermined width 12W on which first terminal row 12 is formed, and a mounting surface of predetermined width 13W on which second terminal row 13 is formed.

[0031] [Film structure] Fig. 3 is a plan view showing a unit area of ​​the film structure, and Fig. 4 is a cross-sectional view taken along line IV-IV in Fig. 3. As shown in Figs. 3 and 4, the film structure 20 includes a tape-like substrate 21 and connecting films 22 and 23 formed on the substrate 21, and has a rectangular unit area having a predetermined length 21L in the longitudinal direction of the substrate 21 and a predetermined width 21W in the width direction of the substrate 21 in a plan view. The film structure 20 has a void 24, which is a non-attached portion, extending from the center of the substrate 21 in the width direction along the length of the substrate 21 in the unit area. The void 24 can be formed, for example, by punching an adhesive film from the center of the substrate 21 in the width direction along the length of the substrate 21. That is, the film structure 20 has non-attached portions formed in a unit area from the center of the width direction of the base material to the length direction of the base material, and a connecting film 22 of a predetermined width 22W and a connecting film 23 of a predetermined width 23W are formed at a distance in the length direction of the base material 21 corresponding to the first terminal row 12 and the second terminal row 13 of the ceramic substrate 11.

[0032] The width 22W of the connection film 22 and the width 23W of the connection film 23 may be narrower, the same as, or wider than the width 12W of the mounting surface of the first terminal row 12 and the width 13W of the mounting surface of the second terminal row 13, respectively.

[0033] When the width of the connecting film is narrower than the width of the mounting surface of the terminal array, excessive resin extrusion of the connecting film from the film connecting body can be suppressed. This prevents excessive resin extrusion from contacting the camera module or other mounted components, improving assembly workability. This is also effective when it is preferable to avoid contamination of the mounted components. When the width of the connecting film is wider than the width of the mounting surface of the terminal array, a sufficient amount of resin can be secured for the connection portion, thereby improving the peel strength (connection strength) of the connected object. This is effective when it is desired to ensure sufficient connection strength for the connection structure. When the width of the connecting film is the same as the width of the mounting surface of the terminal array, both of the above advantages can be achieved. The width of the connecting film and the width of the mounting surface of the terminal array can be adjusted appropriately to suit the specifications required for the mounting portion.

[0034] From the viewpoint of the electrical conductivity and adhesive properties of the connection structure, the lower limits of the width 22W of the connection film 22 and the width 23W of the connection film 23 are preferably 80% or more, more preferably 100% or more, and even more preferably 120% or more of the width 12W of the mounting surface of the first terminal row 12 and the width 13W of the mounting surface of the second terminal row 13, respectively. From the viewpoint of shaping, if the width is too narrow, the difficulty increases, so for example, the width is 0.3 mm or more, preferably 0.4 mm or more, and even more preferably 0.5 mm or more. Furthermore, the upper limits of the width 22W of the connection film 22 and the width 23W of the connection film 23 are preferably 280% or less, more preferably 240% or less of the width 12W of the mounting surface of the first terminal row 12 and the width 13W of the mounting surface of the second terminal row 13, respectively.

[0035] Furthermore, the lower limit of the width 24W of the void 24 is 5% or more, preferably 10% or more, and more preferably 20% or more of the width 21W of the substrate 21. The upper limit of the width 24W of the void 24 is 80% or less, preferably 75% or less, and more preferably 60% or less of the width 21W of the substrate 21. If the width 24W of the void 24 is too small, there is a concern that the recess will be sealed due to resin flow. If the width 24W of the void 24 is too large, there is a concern that the width of the connection film will be narrowed, resulting in peeling of the connection film from the substrate and, in some cases, insufficient adhesive strength of the connection body. As a specific example, the width 24W of the void 24 is preferably 1.0 mm or more, and more preferably 1.2 mm or more. This prevents gas from filling the recess, which could reduce reliability, and ensures high adhesive strength. Furthermore, the amount of connection film used is reduced, which is preferable from an environmental perspective. Reusing the removed void portion not only improves environmental performance, but also reduces material costs, thereby improving economic efficiency. Another use method is to store the removed void for verification purposes.

[0036] [Attachment process] FIG. 5 is a cross-sectional view showing the attachment step of attaching a connection film to a camera module, and FIG. 6 is a cross-sectional view showing the state in which the substrate has been peeled off from the connection film in the attachment step. As shown in FIGS. 5 and 6, in the attachment step, the connection films 22 and 23 of the unit areas of the film structure 20 are transferred to the camera module 10. For example, a bonding device is used to press the film structure from the substrate side, and the connection films 22 and 23 of the unit areas are attached all at once to the mounting surface of the camera module 10 on the stage. The film structure to which the connection films 22 and 23 have been transferred is wound up as just the substrate.

[0037] [Mounting process] 7 is a cross-sectional view showing the mounting process of mounting a flexible substrate on a camera module. As shown in Fig. 7, the flexible substrate 30 has a first terminal row 32 and a second terminal row 33 on a base material 31, corresponding to the first terminal row 12 and the second terminal row 13 of the camera module 10. In the mounting process, the first terminal row 32 and the second terminal row 33 of the flexible substrate 30 are aligned with the first terminal row 12 and the second terminal row 13 of the camera module 10, and the flexible substrate 30 is mounted on the camera module 10.

[0038] [Connection process] 8 is a cross-sectional view showing a connection step of connecting terminals of a camera module and terminals of a flexible substrate via a connection film. As shown in Fig. 8, in the connection step, for example, a crimping tool 42 is used to press the first terminal row 12 of the camera module 10 and the first terminal row 32 of the flexible substrate 31 via a buffer material 41, and a crimping tool 43 is used to press the second terminal row 13 of the camera module 10 and the second terminal row 33 of the flexible substrate 30. In addition, the connection film is cured by heating, light irradiation, or the like, depending on the curing type of the connection film.

[0039] Fig. 9 is a cross-sectional view showing a connection structure mounted with a camera module. As shown in Fig. 9, the connection structure mounted with camera module 10 is configured such that first terminal row 12 of camera module 10 and first terminal row 32 of flexible substrate 30 are connected by cured film 22A formed by curing connection film 22. Also, second terminal row 13 of camera module 10 and second terminal row 33 of flexible substrate 30 are connected by cured film 23A formed by curing connection film 23. In the case of a hot-melt type connection film, cured film 23 is a cured film connected by the hot-melt type connection film.

[0040] According to this method for manufacturing a connection structure, the film structure has a non-attached portion extending from the periphery of the unit area toward the center of the unit area when viewed in a plane, so that electronic components having a recess in the center of the mounting surface can be mounted using existing equipment, preventing gas from filling the recess and reducing reliability.

[0041] <2. Connection structure> The connection structure according to this embodiment includes a first electronic component having a recess in the center of its mounting surface, a second electronic component, and a cured film formed by curing a connection film between the first and second electronic components, the connection film having a non-attached portion extending from the periphery of a unit area having a predetermined length and a predetermined width in a plan view toward the center of the unit area, and the terminals of the first electronic component and the second electronic component are connected to each other. This prevents the recess from being filled with gas, which would otherwise reduce reliability.

[0042] As described above, the first electronic component and the second electronic component are not particularly limited and can be appropriately selected depending on the purpose. In addition, the connecting film and the curing type of the connecting film are also not particularly limited and can be appropriately selected depending on the purpose.

[0043] A connection structure mounted with a camera module will be described below as a specific example. FIG. 10 is a cross-sectional view showing an example of the configuration of a connection structure mounted with a camera module. Components similar to those shown in FIGS. 1 to 9 are designated by the same reference numerals, and their description will be omitted. As shown in FIG. 10, the connection structure includes a camera module 10 having a first terminal row 12 and a second terminal row 13, a flexible substrate 30 having a first terminal row 32 and a second terminal row 33, a cured film 22A formed by curing the connection film 22 between the first terminal row 12 and the first terminal row 32, and a cured film 23A formed by curing the connection film 23 between the second terminal row 13 and the second terminal row 33. The connection structure also includes a protective glass 15 fixed on the ceramic substrate 11 and a lens 16 disposed on the image sensor 14 and installed in the housing. A camera module driving IC 17 may be mounted on the flexible substrate 30 in addition to the camera module mounting portion.

[0044] With a connection structure having such a configuration, it is optically difficult to shorten the distance T2 between the image sensor 14 and the lens 16, but it is possible to shorten the distance T1 between the lens 16 and the flexible substrate 30, thereby enabling a thinner structure. Furthermore, in the rectangular mounting surface of the connection structure, two opposing sides of the periphery of the recess in the ceramic substrate 11 are fixed with the cured films 22A and 23A, while portions of the other two sides are not fixed. This prevents the recess in the ceramic substrate 11 from being blocked by the base material 31 of the flexible substrate 30, which would otherwise cause the flexible substrate 30 to swell due to the influence of gas.

[0045] <3. Film structure> The film structure according to the present embodiment includes a tape-shaped substrate and a connecting film formed on the substrate, and has unit areas of a predetermined length in the longitudinal direction of the substrate in a plan view, and has non-attached areas extending from the periphery of the unit areas toward the center of the unit areas. The film structure can also be in the form of a film roll wound around a core.

[0046] Fig. 11 is a perspective view schematically showing a film winding body. As shown in Fig. 11, the film winding body is formed by winding a film structure including a tape-shaped substrate 21 and connecting films 22 and 23 formed on the substrate 21 around a winding core 25. The winding core 25 has an axial hole into which a rotating shaft for rotating the reel is inserted, and connects one longitudinal end of the film structure to wind the film structure. The length of the film structure wound around the film winding body is not particularly limited, but the lower limit is 5 m or more, 10 m or more, or 50 m or more, and the upper limit is preferably 5,000 m or less, 3,000 m or less, or 1,000 m or less.

[0047] The substrate 21 is formed into a tape shape and is a support film that supports the connection films 22 and 24. Examples of the substrate 21 include PET (Poly Ethylene Terephthalate), OPP (Oriented Polypropylene), PMP (Poly-4-methylpentene-1), and PTFE (Polytetrafluoroethylene). In addition, the substrate 21 is preferably one in which at least the surface on the connection films 22 and 23 side is subjected to release treatment with, for example, silicone resin.

[0048] The thickness of the substrate is not particularly limited. The lower limit of the substrate thickness is preferably 10 μm or more in terms of separation, more preferably 25 μm or more, and even more preferably 38 μm or more. The upper limit of the substrate thickness is preferably 200 μm or less, more preferably 100 μm or less, and even more preferably 75 μm or less, because if the substrate is too thick, there is a concern that excessive pressure will be applied to the connection film. It may also be 50 μm or less. Furthermore, since this technology assumes that the substrate and the connection film are separable, it is not preferable for the unit area to be too small, as this will cause unnecessary separation. Furthermore, for the same reason, it is not preferable for the void portion to be too large.

[0049] The width of the substrate is not particularly limited. The lower limit of the width of the substrate is preferably 1 mm or more in consideration of winding, more preferably 2 mm or more, and even more preferably 4 mm or more. The upper limit of the width of the substrate may be 250 mm or less, preferably 120 mm or less, more preferably 60 mm or less, and even more preferably 10 mm or less, because if the width is too large, it may be difficult to carry or handle. The width of the substrate may be adjusted appropriately depending on the size of the unit area and the void. From the viewpoint of productivity, it is preferable that a part of the connection film contacts the end of the width of the substrate film.

[0050] As described above, the connecting film and the curing type of the connecting film are not particularly limited and can be appropriately selected depending on the purpose. As described above, the curing type may be replaced with a hot melt type.

[0051] The following describes an anisotropic conductive film containing conductive particles in an insulating binder. The lower limit of the thickness of the anisotropic conductive film may be, for example, the same as the diameter of the conductive particles, and preferably 1.3 times or more the diameter of the conductive particles or 10 μm or more. The upper limit of the thickness of the anisotropic conductive film may be, for example, 40 μm or less or 2 times or less the diameter of the conductive particles. The anisotropic conductive film may also be laminated with adhesive layers or pressure-sensitive adhesive layers that do not contain conductive particles, and the number of layers and lamination surfaces can be selected appropriately depending on the target and purpose. The insulating resin for the adhesive layer or pressure-sensitive adhesive layer can be the same as that for the anisotropic conductive film. The conductive particles may be dispersed or arranged in the resin. When the conductive particles are dispersed in the resin, they may be individually spaced apart without contacting each other. The anisotropic conductive film preferably contains conductive particles so that the number of conductive particles captured per terminal is preferably 5 or more, more preferably 10 or more.

[0052] The conductive particles may be appropriately selected from those used in known anisotropic conductive films. Examples include metal particles such as nickel, copper, silver, gold, and palladium, and metal-coated resin particles in which the surface of resin particles such as polyamide and polybenzoguanamine is coated with a metal such as nickel. The surface may be insulated to the extent that it does not impair the conductive performance. Furthermore, the surface may have protrusions.

[0053] The particle diameter of the conductive particles is not particularly limited, but the lower limit of the particle diameter is preferably 2 μm or more, and the upper limit of the particle diameter is preferably 50 μm or less, more preferably 20 μm or less, from the viewpoint of the capture efficiency of the conductive particles in the connection structure. The particle diameter of the conductive particles can be a value measured using an imaging particle size distribution analyzer (for example, FPIA-3000: manufactured by Malvern Instruments). The number of particles is preferably 1,000 or more, and more preferably 2,000 or more.

[0054] Known insulating binders can be used as the insulating binder (insulating resin). Examples of curing types include heat-curing, photo-curing, and photo-thermal curing. Examples include photo-radical polymerization resin compositions containing a (meth)acrylate compound and a photo-radical polymerization initiator, thermal radical polymerization resin compositions containing a (meth)acrylate compound and a thermal radical polymerization initiator, thermal cationic polymerization resin compositions containing an epoxy compound and a thermal cationic polymerization initiator, and thermal anionic polymerization resin compositions containing an epoxy compound and a thermal anionic polymerization initiator. Known pressure-sensitive adhesive compositions may also be used. For hot-melt adhesives, the composition disclosed in JP 2014-060025 A can be used.

[0055] Hereinafter, a specific example will be described, taking as an example a thermal radical polymerization insulating binder containing a film-forming resin, an elastomer, a (meth)acrylic monomer, a polymerization initiator, and a silane coupling agent. Note that the term "(meth)acrylic monomer" means both an acrylic monomer and a methacrylic monomer.

[0056] The film-forming resin is not particularly limited, and examples thereof include phenoxy resin, unsaturated polyester resin, saturated polyester resin, urethane resin, butadiene resin, polyimide resin, polyamide resin, and polyolefin resin. The film-forming resin may be used alone or in combination of two or more. Among these, phenoxy resin is particularly preferred from the viewpoints of film-forming ability, processability, and connection reliability. The phenoxy resin is a resin synthesized from bisphenol A and epichlorohydrin, and an appropriately synthesized product or a commercially available product may be used. The content of the film-forming resin is not particularly limited, and is preferably, for example, 10% to 60% by mass.

[0057] The elastomer is not particularly limited, and examples thereof include polyurethane resin (polyurethane-based elastomer), acrylic rubber, silicone rubber, and butadiene rubber.

[0058] The (meth)acrylic monomer is not particularly limited and may be, for example, a monofunctional (meth)acrylic monomer or a polyfunctional (meth)acrylic monomer having two or more functionalities. From the viewpoint of stress relaxation of the polymer, it is preferable that 80 mass % or more of the (meth)acrylic monomers in the insulating binder are monofunctional (meth)acrylic monomers.

[0059] From the viewpoint of adhesiveness, the monofunctional (meth)acrylic monomer preferably has a carboxylic acid. The molecular weight of the monofunctional (meth)acrylic monomer having a carboxylic acid is preferably 100 to 500, more preferably 200 to 350. The content of the monofunctional (meth)acrylic monomer having a carboxylic acid in the insulating binder is preferably 3% by mass to 20% by mass, more preferably 5% by mass to 10% by mass.

[0060] The polymerization initiator is not particularly limited as long as it can cure the (meth)acrylic monomer at a predetermined temperature during thermocompression bonding, and examples thereof include organic peroxides. Examples of organic peroxides include lauroyl peroxide, butyl peroxide, benzyl peroxide, dilauroyl peroxide, dibutyl peroxide, peroxydicarbonate, and benzoyl peroxide. These may be used alone or in combination of two or more. The content of the polymerization initiator in the insulating binder is not particularly limited, and is preferably, for example, 0.5% to 15% by mass.

[0061] The silane coupling agent is not particularly limited, and examples thereof include epoxy-based silane coupling agents, acrylic-based silane coupling agents, thiol-based silane coupling agents, amine-based silane coupling agents, etc. The content of the silane coupling agent in the insulating binder is not particularly limited, and is preferably, for example, 0.1% by mass to 5.0% by mass.

[0062] <4. Method for manufacturing film structure> The method for manufacturing a film structure includes a processing step of processing a raw film including a tape-shaped substrate and a connecting film formed on the substrate. In the processing step, a film structure is formed having unit areas each having a predetermined length in the longitudinal direction of the substrate and a predetermined width in the lateral direction of the substrate in a plan view, with a non-attached portion extending from the periphery of the unit area toward the center of the unit area. In the processing step, the raw film is slit, half-cut, punched, punched, or punched with a punch press to form a connecting film of a desired shape in the unit area. Alternatively, only the connecting film on the substrate film may be processed and removed. A step of providing a cover film on the connecting film surface may also be provided. Therefore, the substrate and connecting film may be processed as described above using the cover film as a support (substitute for the substrate). As described above, the substrate and connecting film are peeled (separated) from the substrate during use, which makes the processing technique highly difficult. The material of the cover film may be the same as the substrate 21 described above. It is preferable that the thickness of the cover film be thinner than that of the substrate 21.

[0063] For example, the film structure shown in Figures 3 and 4 can be obtained by full-cutting the film to have a unit area of ​​a predetermined width in a planar view, and then half-cutting the film to have a non-adhesive area extending from the periphery of the unit area toward the center of the unit area. Specifically, the film can be obtained by full-cutting the film roll to the unit area width 21W and half-cutting it to a width 24W that will form the void 24, and then punching the connecting film to a width of 24W. By punching the connecting film in the film structure, the resin in the connecting film can migrate into the voids in the non-adhesive area, thereby suppressing overflow and blocking that can occur when the film is reeled, thereby increasing the flexibility of the connecting film's formulation design. Furthermore, if the film is wound after processing, contact between the connecting film and the processed area can leave traces of the processing on the connecting film, which can result in an undesirable appearance. To prevent this, a cover film may be provided.

[0064] The depth of the half cut is preferably 1% to 95% of the thickness of the substrate. If the half cut is deep, the resin of the protruding connection film will penetrate into the half-cut portion when the film is reeled, thereby suppressing protrusion and blocking. Furthermore, if the half cut is shallow, the connection film may not be penetrated, so the depth of the half cut is preferably 5% or more of the thickness of the substrate. This depends on the thickness of the substrate, but for stable half-cutting, a depth of 10% or more is more preferable. If the adhesive film has high viscosity, a depth of more than 50% is preferable to ensure reliable cutting, more preferably 55% or more, and even more preferably 60% or more. Furthermore, if the depth of the half cut is too deep, there is a risk of the substrate being penetrated by minor vibrations or the like when making continuous half-cuts. Therefore, the depth of the half cut is preferably 90% or less of the thickness of the substrate, more preferably 80% or less, even more preferably 50% or less, and in some cases, 25% or less. This depth can be selected appropriately depending on the thickness of the substrate and the length of the film. Furthermore, such half-cutting makes it easier to remove the connection film from the base material, which is expected to improve the manufacturing productivity of the connection structure.

[0065] The processed film structure may have the connection film on one side half-cut, or may have a portion of the connection film removed so that the connection film is individually present on the substrate. From a manufacturing standpoint, it is preferable for the connection film to be supported on the substrate, but the substrate may be removed by using a cover film as a support. The selection should take into account the overall workability and economy from the manufacturing process of the film structure to the connection process in which it is used. This wide range of choices increases convenience.

[0066] <5. Variations> 12 to 15 are plan views showing film structures of Modified Examples 1 to 4. As shown in Fig. 12, the film structure of Modified Example 1 has gaps 241, which are non-attachment portions, formed in a unit region from the centers of two longitudinal sides of the base material to the entire width of the base material, and is compatible with electronic components having a recess in the center of the rectangular mounting surface and terminal rows on two opposing sides around the periphery of the recess.

[0067] Furthermore, as shown in FIG. 13, the film structure of variant 2 has a non-attached portion, void 242, formed in a unit area from the center of one longitudinal side of the substrate to a portion of the width of the substrate, and is capable of accommodating electronic components having a recess in the center of the rectangular mounting surface and terminal rows on three peripheral sides of the recess.

[0068] Furthermore, as shown in FIG. 14, the film structure of variant example 3 has gaps 243 and 244, which are non-attached portions, formed in a unit area from the center of two longitudinal sides of the substrate to a portion of the width of the substrate, and is compatible with electronic components that have a recess in the center of the rectangular mounting surface and terminal rows on two opposing sides around the periphery of the recess.

[0069] Such film structures of Modifications 1 to 3 can be formed by, for example, punching.

[0070] 15, the film structure of Modification 4 has a gap 245, which is a non-attachment portion, formed in the unit area from the center of one side of the substrate in the longitudinal direction to a part of the width direction of the substrate, and has a recess in the center of the rectangular mounting surface, and is capable of accommodating electronic components having terminal rows on three sides around the recess. The film structure of Modification 4 is also simple, for example, by punch press processing, in which neither the substrate nor the connection film is present in the non-attachment portion, and the connection film can be half-cut to the length 21L of the unit area using an existing attachment device.

[0071] Fig. 16 is a plan view showing the mounting surface of a camera module. As shown in Fig. 16, camera module 50 includes ceramic substrate 51 having a recess (cavity) on its rectangular mounting surface, first terminal row 52 and second terminal row 53 formed on two opposing sides of the periphery of the recess on the rectangular mounting surface, third terminal row 54 formed on one of the two sides not adjacent to the two sides on which first terminal row 52 and second terminal row 53 are formed, and image sensor 55 housed in the recess. The mounting surface of camera module 50 is rectangular, has a recess in the center, and has terminal rows on three sides (U-shaped) around the periphery of the recess.

[0072] FIG. 17 is a plan view showing a first example of a film structure corresponding to the mounting surface shown in FIG. 16. The film structure shown in FIG. 17 has an octagonal peripheral shape of the attachment portion in unit regions 21L and 21W. This makes it possible to suppress excessive resin overflow after pressing, compared to when the peripheral shape of the attachment portion is rectangular, when mounting an electronic component with a rectangular mounting surface, and to prevent contamination of the side surface of the electronic component. Furthermore, by chamfering the corners of the rectangular attachment portion with straight lines to form an octagonal attachment portion, the amount of connection film used can be reduced. Furthermore, a non-attached portion may be provided in the center of the octagonal attachment portion. This prevents the recess of the camera module 50 from being sealed.

[0073] FIG. 18 is a plan view showing a second example of a film structure corresponding to the mounting surface shown in FIG. 16. The film structure shown in FIG. 18 is the octagonal attachment portion of the film structure shown in FIG. 17, with a gap 246, which is a non-attachment portion, formed from the center of one side in the longitudinal direction of the base to a portion in the width direction of the base. This makes it possible to prevent the recess of camera module 50 from being sealed when mounting an electronic component having the mounting surface shown in FIG. 16, and also makes it possible to reduce the amount of connecting film used. Furthermore, because the outline of the mounting surface and the outline of the film structure match where necessary, excessive overflow of unnecessary resin after bonding the connecting film can be suppressed.

[0074] FIG. 19 is a plan view showing a third example of a film structure corresponding to the mounting surface shown in FIG. 16. In the film structure shown in FIG. 19, the peripheral shape of the attachment portion in unit regions 21L and 21W is U-shaped corresponding to the mounting surface shown in FIG. 16. This is achieved by processing the corners of the rectangular attachment portion into curves, and forming a gap 247, which is a non-attachment portion, from the center of one side in the length direction of the base material to a part in the width direction of the base material, and by chamfering the corners into a curved U-shaped attachment portion. By providing a curved shape to the attachment portion in this way, sharp parts are reduced, making it possible to prevent the connection film from turning over due to unnecessary contact, etc.

[0075] The film structures shown as the first to third examples can be obtained, for example, by preparing a master equipped with a blade for cutting the base film (e.g., polyethylene terephthalate) as the substrate and a half-cutting blade for cutting the connecting film into the desired shape and penetrating about halfway through the thickness of the substrate, and then using this master to punch out the film roll and remove the non-attached portions. The master may also have joints. In this case, there may be some areas in the longitudinal direction of the film structure where the spacing between the attached portions of the connecting film varies, but this is advantageous in terms of production management, such as counting.

[0076] Another embodiment of a method for manufacturing a connection structure includes a film structure including a tape-like substrate, a connection film formed on the substrate, and a cover film attached to the connection film. The connection film has a unit area having a predetermined length in the longitudinal direction of the substrate and a predetermined width in the width direction of the substrate. The connection film is attached to a substrate component including an element and a plurality of electrodes formed around the element, or to an electronic component including electrodes corresponding to the electrodes of the substrate component, via the connection film. The connection film also includes a non-attached portion made of the cover film at a location corresponding to the element in the unit area. By making the non-attached portion made of the cover film, when the film structure is wound around a core to form a wound body, it is possible to prevent contact with the substrate or the like processed with the adhesive film's resin, resulting in the shape being reflected and deteriorating the appearance. Excessive resin overflow into the gaps can also be suppressed.

[0077] The cover film can be made of the same material as the substrate, such as PET, OPP, PMP, PTFE, etc. The thickness of the cover film is preferably thinner than that of the substrate, and is preferably 8 to 38 μm, and more preferably 12 to 25 μm.

[0078] In the attaching step, it is preferable to align the connecting film before attaching it to the substrate component or electronic component, which can reliably prevent the adhesive film from adhering to the element.

[0079] Another embodiment of the connection structure includes a substrate component having an element and a plurality of electrodes formed around the element; an electronic component having electrodes corresponding to the electrodes of the substrate component; and a cured film formed by curing a connection film in which the element is provided with a void in a unit area having a predetermined length and a predetermined width between the substrate component and the electronic component, connecting the electrodes of the substrate component and the electrodes of the electronic component. Using a connection film in which the element is provided with a void can prevent the adhesive film from adhering to the element, which could degrade the element's functionality. Furthermore, the connection film can be temporarily attached to the substrate while avoiding the element, improving work efficiency during the connection process. Because such elements are often relatively expensive, pre-processing the connection film structure can be economical from an overall perspective.

[0080] The substrate components and electronic components are not particularly limited and can be appropriately selected depending on the purpose. Examples of substrate components include ceramic substrates, rigid substrates, flexible substrates (FPC: Flexible Printed Circuits), glass substrates, plastic substrates, resin multilayer substrates, IC (Integrated Circuit) modules, IC chips, etc. Examples of electronic components include ceramic substrates, rigid substrates, flexible substrates (FPC: Flexible Printed Circuits), glass substrates, plastic substrates, resin multilayer substrates, etc.

[0081] The substrate component may include, for example, a component having a semiconductor element in the center of the mounting surface and electrodes formed on the periphery of the mounting surface. For example, a substrate component having a semiconductor element in the center of a rectangular mounting surface may have electrodes on two opposing sides of the mounting surface, two adjacent sides (L-shaped), three sides of the periphery of the mounting surface (U-shaped, C-shaped), or all four sides (in the case of a shape with five or more sides). The connecting film and substrate may be perforated and hollowed out (the center of the surface may be hollowed out). The outer shape of the mounting surface may be not only rectangular, but also curved, circular, polygonal, or the like. In particular, a camera module with an image sensor mounted in the center of a ceramic substrate is suitable as a substrate component, due to its excellent electrical and thermal insulation properties.

[0082] FIG. 20 is a plan view showing an example of a mounting surface of a camera module according to another embodiment. As shown in FIG. 20, a camera module 60 includes a ceramic substrate 61, first electrodes 62A, 62B, and 62C formed on two opposing sides of the periphery of an image sensor 65, second electrodes 63A, 63B, and 63C, a third electrode 64 formed on one of two sides not adjacent to the two sides on which the first electrodes 62A, 62B, and 62C and the second electrodes 63A, 63B, and 63C are formed, and an image sensor 65 mounted in the center of the ceramic substrate 61. That is, this camera module 60 has first to third electrodes on three sides (U-shaped) of the periphery of the rectangular image sensor 65. Note that the mounting surface is not limited to that shown in FIG. 20, and the image sensor may have electrodes on all four sides of the periphery.

[0083] Fig. 21 is a plan view showing an example of a connecting film corresponding to the mounting surface of the camera module shown in Fig. 20. The connecting film 70 has an attached portion 71 consisting of the four sides of the periphery of the image sensor 65, and a non-attached portion 72 which is a gap portion where the portion corresponding to the image sensor 65 is cut out. Because the portion corresponding to the image sensor 65 is a gap portion, the connecting film 40 can be prevented from adhering to the image sensor 65.

[0084] FIG. 22 is a perspective view showing an example of a tape-like film structure around which the connecting film shown in FIG. 21 is wound, and FIG. 23 is a widthwise cross-sectional view of the film structure including a non-adhesive portion. The film structure 80 includes a tape-like substrate 81, a connecting film 82 formed on the substrate 81, and a cover film 83 attached to the connecting film 82. The film structure 80 has a rectangular unit area having a predetermined length L in the longitudinal direction of the substrate 81 and a predetermined width W in the transverse direction of the substrate 81, and a rectangular non-adhesive portion 84 made of the cover film 83 at the center of the unit area. By attaching the cover film 83, even if the resin of the connecting film seeps into the non-adhesive portion 84, the film structure can be easily pulled out from the wound body in which the film structure is wound. Furthermore, by attaching the cover film 83, the appearance of the connecting film can be maintained.

[0085] In the film structure shown in FIG. 22, hollow portions are punched out of the base material 81 and the connection film 82 to form rectangular unit areas each having a predetermined length L and a predetermined width W. The cover film 83 in FIG. 22 is not perforated, but the base material 81 and the connection film 82 are punched out. In this case, the connection film 82 may be half-cut or removed at every predetermined length L to suit the area where it is used. If the cover film is used as a support, the base material 81 and the connection film 82 may be half-cut or removed at every predetermined length L to suit the area where it is used. Alternatively, the film may be pre-processed into the shape of FIG. 21 and then attached to the cover film.

[0086] The base material 81 and the cover film 83 are formed into a tape-like shape and are support films that support the connection film 82. As in the above-described embodiment, the base material 81 and the cover film 83 may be made of, for example, PET (Poly Ethylene Terephthalate), OPP (Oriented Polypropylene), PMP (Poly-4-methylpentene-1), or PTFE (Polytetrafluoroethylene). Preferably, the base material 81 and the cover film 83 have at least the surface facing the connection film 82 treated with a release agent, such as a silicone resin.

[0087] As in the above-described embodiment, the connecting film 81 is not particularly limited, and examples thereof include a film-shaped anisotropic conductive film (ACF: Anisotropic Conductive Film) and a film-shaped adhesive film (NCF: Non-Conductive Film). The curing type of the connecting film 81 is also not particularly limited, and examples thereof include a thermosetting type, a photosetting type, and a photo-thermal combined curing type. The connecting film 81 may also be a hot-melt type using a thermoplastic resin.

[0088] The wound body is formed by winding the film structure around a core so that the cover film 83 faces outward or inward. Such a film structure includes a processing step of processing a raw film having a tape-like substrate and a connecting film formed on the substrate, and a bonding step of bonding a cover film to the processed raw film. In the processing step, the film structure can be manufactured by punching out the substrate and connecting film at the center of a unit area having a predetermined length in the longitudinal direction of the substrate and a predetermined width in the width direction of the substrate. If necessary, the raw film can be fully cut to the predetermined width of the unit area, and these can be joined together and wound around a core.

[0089] In the processing step, the predetermined length and width when punching out the base material and connection film at the center of the unit area are, for example, 0.3 mm or more, preferably 0.4 mm or more, and more preferably 0.5 mm or more. If the size of the base material and connection film punched out is small, the resin of the connection film may overflow into the punched area, and a non-attached area may not be formed.

[0090] In addition, although the present technology adheres an adhesive film to the locations corresponding to the terminal arrays and electrodes, conductive particles may be provided only to the locations corresponding to the terminal arrays and electrodes. Examples of technologies for providing conductive particles only to the locations corresponding to the terminal arrays and electrodes include JP 2016-119306 A and JP 2016-131152 A.

[0091] For example, a resin mold is formed in which recesses are arranged in a grid pattern at positions corresponding to the terminal rows or electrodes, and conductive particles are filled into the recesses of the resin mold. The conductive particles are then transferred from the resin mold to an insulating resin film, thereby obtaining a connection film in which conductive particles are arranged only at positions corresponding to the terminal rows or electrodes. The conductive particles in the connection film are preferably arranged so that, for example, five or more conductive particles are captured by one terminal or electrode, and more preferably ten or more conductive particles are captured by one terminal or electrode. The arrangement of conductive particles can also be used as an alignment mark for the connection film. [Example]

[0092] 6. Working Examples EXAMPLES Examples of the present technology will be described below. In these examples, a connection structure was fabricated using an anisotropic conductive film, and its conduction characteristics were evaluated.

[0093] [Fabrication of anisotropic conductive film] Five parts by weight of resin-core conductive particles (Ni (base) / Au (surface) plating, resin core) with an average particle size of 20 μm and 95 parts by weight of an insulating binder consisting of the following components were added to a planetary mixer (product name: Awatori Rentaro, manufactured by THINKY Co., Ltd.) and stirred for 1 minute to prepare an anisotropic conductive adhesive composition. The anisotropic conductive adhesive composition was then applied to a 50 μm-thick PET film and dried in an oven at 80°C for 5 minutes to form an adhesive layer consisting of the anisotropic conductive adhesive composition on the PET film, producing an anisotropic conductive film 6.0 mm wide and 25 μm thick. The ratio of conductive particles to insulating binder was adjusted to ensure that 5 or more particles were captured after connection.

[0094] The insulating binder was a mixed solution of ethyl acetate and toluene containing 47 parts by mass of phenoxy resin (trade name: YP-50, manufactured by Shin-Nichika Epoxy Manufacturing Co., Ltd.), 3 parts by mass of monofunctional monomer (trade name: M-5300, manufactured by Toagosei Co., Ltd.), 25 parts by mass of urethane resin (trade name: UR-1400, manufactured by Toyobo Co., Ltd.), 15 parts by mass of rubber component (trade name: SG80H, manufactured by Nagase ChemteX Corporation), 2 parts by mass of silane coupling agent (trade name: A-187, manufactured by Momentive Performance Materials Japan), and 3 parts by mass of organic peroxide (trade name: Nyper BW, manufactured by NOF Corporation) so that the solid content was 50% by mass.

[0095] [Fabrication of connection structure] A camera module evaluation substrate (ceramic substrate, 6.0 mm wide, terminal row mounting surface width 1.0 mm, 200 μm pitch, line:space ratio 1:1, terminal thickness 10 μm, Ni (undercoat) / Au (surface) plating, cavity structure, terminal rows on two opposing sides) was thermocompression bonded to an FPC (polyimide film, 200 μm pitch, line:space ratio 1:1, terminal thickness 12 μm, Ni (undercoat) / Au (surface) plating) via an anisotropic conductive film to create a connection structure. Thermocompression bonding was performed using a tool pressing down on the FPC side through a 200 μm-thick silicone rubber at a temperature of 120°C, a pressure of 1 MPa, and a time of 6 seconds. In practice, it is desirable to achieve five or more captures per terminal. Microscopic observation of the indentations on the connection structure fabricated in this study from the FPC side confirmed that five or more conductive particles were captured per terminal.

[0096] [Evaluation of conduction characteristics] Using a digital multimeter (manufactured by Yokogawa Electric Corporation), the initial conduction resistance of the connection structure was measured using the four-terminal method when a current of 1 mA was applied. The conduction resistance of the connection structure was also measured after a reliability evaluation test (12 hours, 24 hours) under conditions of a temperature of 121°C, humidity of 100%, and atmospheric pressure of 2 atm. The conduction characteristics were evaluated as "A" if the conduction resistance after the reliability evaluation test was equivalent to the initial conduction resistance (variation of 5% or less), and as "B" if the conduction resistance after the reliability evaluation test increased from the initial conduction resistance (variation of more than 5%). The conduction resistance of 20 connection structure samples was measured (N=20), and the sample with the highest conduction resistance was used for evaluation.

[0097] [Evaluation of adhesive properties] The connection structure was subjected to a 90-degree peel test at a peel speed of 50 mm / min against an FPC, and the force required to peel was measured. The adhesive properties were evaluated with the peel strength of Comparative Example 1 set to 1. The peel strength of 20 samples of the connection structure was measured (N=20), and the sample with the lowest peel strength was used for evaluation.

[0098] <Experimental Example 1> A connection structure was fabricated by attaching a 6.0 mm wide anisotropic conductive film to a camera module evaluation board. Table 1 shows the evaluation of the electrical conductivity and adhesive properties of the connection structure.

[0099] Example 1 3 and 4, an anisotropic conductive film was produced by half-cutting a 50 μm thick PET film to a depth of 20 μm (40% of the thickness of the substrate) so that the width 22W of the connecting film 22 was 0.8 mm, the width 23W of the connecting film 23 was 0.8 mm, and the width 24W of the gap 24 was 4.4 mm. Table 1 shows the evaluation of the conductivity characteristics and adhesion characteristics of the connecting structure.

[0100] <Example 2> 3 and 4, an anisotropic conductive film was produced in the same manner as in Example 1, except that the width 22W of the connecting film 22 was 1.2 mm, the width 23W of the connecting film 23 was 1.2 mm, and the width 24W of the gap 24 was 3.6 mm. Table 1 shows the evaluation of the conduction properties and adhesion properties of the connecting structure.

[0101] Example 3 3 and 4, an anisotropic conductive film was produced in the same manner as in Example 1, except that the width 22W of the connecting film 22 was 2.4 mm, the width 23W of the connecting film 23 was 2.4 mm, and the width 24W of the gap 24 was 1.2 mm. Table 1 shows the evaluation of the conduction properties and adhesion properties of the connecting structure.

[0102] <Experimental Example 2> 3 and 4, an anisotropic conductive film was produced in the same manner as in Example 1, except that the width 22W of the connecting film 22 was 2.88 mm, the width 23W of the connecting film 23 was 2.6 mm, and the width 24W of the gap 24 was 0.24 mm. Table 1 shows the evaluation of the conduction properties and adhesion properties of the connecting structure.

[0103] [Table 1]

[0104] As shown in Table 1, in Experimental Example 1, in which anisotropic conductive film was attached to the entire camera module evaluation board, the conduction resistance value increased after the reliability evaluation test. In Experimental Example 2, in which the gap width was set to 4% (0.24 mm) of the width of the camera module evaluation board, the conduction resistance value also increased after the reliability evaluation test. In Experimental Example 2, because the gap width was narrow, the gap was blocked by the resin flow during connection, and during the reliability evaluation test, the FPC swelled due to gas expansion, which is thought to have caused the resistance value to increase. Note that the performance of Experimental Examples 1 and 2 does not pose any particular problems in practical use.

[0105] On the other hand, in Examples 1 to 3, in which the gap width was 5% to 75% of the width of the camera module evaluation substrate, the conduction resistance value after the reliability evaluation test was equivalent to the initial conduction resistance value. Also, in Examples 2 and 3, in which the width of the anisotropic conductive film was 100% to 250% of the width of the mounting surface of the terminal row, the peel strength was 1, similar to Experimental Example 1.

[0106] A connection structure was also fabricated by thermocompression bonding a camera module evaluation substrate (ceramic substrate, 6.0 mm wide, 1.0 mm wide mounting surface for the first to third terminal rows, 200 μm pitch, line:space=1:1, terminal thickness=10 μm, Ni (undercoat) / Au (surface) plating, with a cavity structure, and terminal rows on each side of the U-shape) with an FPC (polyimide film, 200 μm pitch, line:space=1:1, terminal thickness=12 μm, Ni (undercoat) / Au (surface) plating) using an anisotropic conductive film having an attachment portion shaped as shown in Figure 18. The anisotropic conductive film had the same composition as above, and the ratio of the maximum film width to the width (1.0 mm) of the terminal rows on the mounting surface for the first to third terminal rows was 100% (1.0 mm). Here, the film width is the width from the gap side to the outside at the attachment part having the shape shown in Fig. 18. Then, when the electrical conductivity and adhesive properties of the connection structure were evaluated in the same manner as above, the electrical conductivity was A and the adhesive properties were 1, similar to Example 2.

[0107] Furthermore, using an anisotropic conductive film having an attachment portion shaped as shown in Figure 17, a camera module evaluation substrate having a U-shaped terminal row as shown in Figure 16 (ceramic substrate, width 6.0 mm, width of mounting surface for first to third terminal rows 1.0 mm, 200 μm pitch, line:space=1:1, terminal thickness 10 μm, Ni (base) / Au (surface) plating, with cavity structure, terminal row on each side of the U-shape) was thermocompression bonded to an FPC (polyimide film, 200 μm pitch, line:space=1:1, terminal thickness 12 μm, Ni (base) / Au (surface) plating) to produce a connection structure.

[0108] The corners of the anisotropic conductive film are chamfered in the unit regions 21L and 21W, and the peripheral shape of the attachment portion is octagonal. The length 21L and width 21W of the attachment portion are the same as the length and width, respectively, of the camera module evaluation substrate. That is, the anisotropic conductive film is chamfered at the portions corresponding to the corners of the evaluation substrate. The electrical conductivity and adhesive properties of the connection structure were evaluated in the same manner as above, and the results were similar to those of Experimental Example 1. The performance was satisfactory in practical use, and excessive resin extrusion after connection was suppressed, making it easy to handle.

[0109] The substrate and anisotropic conductive film were punched into a square shape similar to that shown in FIG. 21 (with the connection film and substrate hollowed out), with widths of 0.8 mm, 1.2 mm, and 2.4 mm (similar to Examples 1 to 3) on all four sides. A 6.0 mm-wide film structure was fabricated using a 12 μm-thick PET film as a cover film. This film structure was used to thermocompression-bond a camera module evaluation substrate (ceramic substrate, 6.0 mm wide, 1.0 mm width of the mounting surface for the first to third terminal rows, 200 μm pitch, line:space=1:1, terminal thickness=10 μm, Ni (undercoat) / Au (surface) plating, no cavity structure, terminal rows on each side of the U-shape) to an FPC (polyimide film, 200 μm pitch, line:space=1:1, terminal thickness=12 μm, Ni (undercoat) / Au (surface) plating) to fabricate a connection structure. The electrical conductivity and adhesive properties of the connection structure were evaluated in the same manner as above. When anisotropic conductive films with a side width of 0.8 mm, 1.2 mm, or 2.4 mm were used for all four sides, the electrical conductivity was rated A, which was the same as in Examples 1 to 3. The adhesive properties were also the same as in Examples 1 to 3. As above, the evaluation results indicated no practical problems. Since the base material and anisotropic conductive film were hollowed out to match the outer shape of the substrate, manual alignment was easy when bonding them to the ceramic substrate. Mechanical bonding is expected to be more efficient.

[0110] Furthermore, for the three types of samples, the hollowed anisotropic conductive film was manually wound in 10 or more layers onto a 150 mm diameter core without a cover film, and then pulled out and visually inspected at 10 or more random locations. For all three types of samples, punching marks remained on the surface of the connection film. When a cover film was applied and similar evaluation was performed, no punching marks remained on the surface of the connection film. Damage to the appearance makes it unclear what the cause of the defect is when performing continuous anisotropic connections, so it is clear that using a cover film is preferable to avoid this. [Explanation of symbols]

[0111] 10 camera module, 11 ceramic substrate, 12 first terminal row, 13 second terminal row, 14 image sensor, 15 protective glass, 16 lens, 17 camera module driving IC, 20 film structure, 21 substrate, 22 connecting film, 23 connecting film, 24 gap, 30 flexible substrate, 31 substrate, 32 first terminal row, 33 second terminal row, 41 cushioning material. 42 Crimping tool, 43 Crimping tool, 50 Camera module, 51 Ceramic substrate, 52 First terminal row, 53 Second terminal row, 54 Third terminal row, 55 Image sensor, 60 Camera module, 61 Ceramic substrate, 62A to 62C First electrodes, 63A to 63C Second electrodes, 64 Third electrodes, 65 Image sensor, 70 Connecting film, 71 Adhered portion, 72 Non-adhered portion, 80 Film structure, 81 Base material, 82 Connecting film, 83 Cover film, 84 Non-adhered portion

Claims

1. A tape-shaped base material, The system comprises a connecting film that is peelably formed on the substrate, In a plan view, the substrate has a unit region of a predetermined length in the longitudinal direction and a unit region of a predetermined width in the width direction of the substrate. A film structure having a void where the connecting film is absent by removing the corners of the connecting film in the unit region, wherein the substrate is half-cut to correspond to the shape of the void.

2. The film structure according to claim 1, having a void portion at the periphery of the unit region in which the connecting film is not present.

3. The film structure according to claim 1, having a void portion in which the connecting film is not present in the direction from the periphery of the unit region toward the center of the unit region.

4. The film structure according to any one of claims 1 to 3, wherein the shape of the missing corner of the connecting film is a straight line.

5. The film structure according to any one of claims 1 to 3, wherein the shape of the missing corner of the connecting film is curved.

6. The film structure according to any one of claims 1 to 5, wherein the connecting film in the unit region has a polygonal shape, a U-shape, a curved shape, a shape having a mixture of curves and straight lines, or a hollow shape.

7. The film structure according to any one of claims 1 to 6, wherein the connecting film comprises conductive particles.

8. The process includes slitting, half-cutting, punching, or punch-pressing a film roll comprising a tape-shaped base material and a connecting film peelably formed on the base material, to form a film structure having a unit area of ​​a predetermined length in the longitudinal direction of the base material and a predetermined width in the width direction of the base material in a plan view. A method for manufacturing a film structure having a void where the connecting film is absent by removing the corners of the connecting film in the unit region, and the substrate being half-cut to correspond to the shape of the void.

9. A first electronic component having multiple terminal rows, The second electronic component, A connecting film of the film structure according to any one of claims 1 to 7 is formed by curing between the first electronic component and the second electronic component, and the terminals of the first electronic component and the terminals of the second electronic component are connected by a cured film. A connecting structure comprising:

10. A bonding step of peeling a connecting film from a film structure according to any one of claims 1 to 7 and attaching it to a first electronic component or a second electronic component having a plurality of terminal rows, A connection step of connecting the terminals of the first electronic component and the terminals of the second electronic component via the connecting film. A method for manufacturing a connecting structure having the following characteristics.

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