Connected body manufacturing method and connected body

Abstract

The invention provides a manufacturing method of a connecting body and the connecting body. The manufacturing method of the connector comprises the following steps: fixing a connector on a first terminal row of a substrate through a thermosetting connecting material containing solder particles, and the connector is provided with a second terminal row with the minimum value of the distance between terminals being less than 0.8 mm on the inner side of a joint surface of the connector and the substrate; and joining the first terminal row and the second terminal row without load using a reflow oven set to be at least the melting point of the solder particles, the ratio of the average particle diameter of the solder particles to the minimum value of the inter-terminal distance in the first terminal row and the second terminal row being less than 0.15, and the ratio of the average particle diameter of the solder particles to the minimum value of the inter-terminal distance in the second terminal row being less than 0.15. The ratio of the average particle diameter of the solder particles to the thickness of the thermosetting connecting material is 0.33-2.0.

Description

[0001] This application is a divisional application of the following application:

[0002] Invention name: Method for manufacturing a connector and a connector.

[0003] International filing date: January 29, 2021.

[0004] International application number: PCT / JP2021 / 003371.

[0005] National application number: 202180011841.0. Technical Field

[0006] The present invention relates to a method for manufacturing a connector body and a connector body. This application claims priority based on Japanese Patent Application No. 2020-019992 filed in Japan on February 7, 2020, which is incorporated herein by reference. Background Art

[0007] In the past, the connector was installed by placing solder paste on a substrate or placing solder (BGA) on the lead portion of the connector, and reflowing the solder installation of the substrate and the connector (see, for example, Patent Document 1). In recent years, in response to the demand for miniaturization of electronic devices, the pitch of the connector is expected to be less than 0.8 mm, and further less than 0.3 mm.

[0008] However, in the installation of the connector in the past, a resist was used for the terminal array on the substrate side, so it was difficult to further narrow the pitch of the connector. As a technology for connecting the terminal array with a narrow pitch, anisotropic connection can be cited. The connector is usually a resin molded product, so when anisotropic connection is performed, the connector is deformed due to the pressure of the tool during the formal crimping, and for example, the cable may not be inserted.

[0009] Prior art literature

[0010] Patent Literature

[0011] Patent document: Japanese Patent Application Laid-Open No. 10-284199 Summary of the invention

[0012] Problems to be solved by the invention

[0013] The present technology has been proposed in view of such conventional actual conditions, and provides a method for manufacturing a connection body and a connection body capable of suppressing deformation of a connector having a terminal row with a narrow pitch and obtaining excellent insulation and conductivity.

[0014] Solutions for solving problems

[0015] The manufacturing method of the connector of the present technology includes the following steps: fixing a connector on a first terminal row on a substrate via a thermosetting connecting material containing solder particles, wherein the connector has a second terminal row on the inner side of the joint surface with the substrate, the minimum distance between the terminals being less than 0.8 mm; and using a reflow furnace set to a temperature above the melting point of the solder particles to join the first terminal row and the second terminal row under no load.

[0016] The connector of the present technology comprises: a substrate having a first terminal row; a connector having a second terminal row on the inner side of the bonding surface with the substrate, the minimum distance between terminals being less than 0.8 mm; and an adhesive layer, which uses solder particles to bond the first terminal row and the second terminal row, and to bond the substrate to the connector.

[0017] Effects of the Invention

[0018] According to the present technology, deformation of a connector having a terminal row with a narrow pitch can be suppressed, and excellent insulation and conductivity can be obtained. In addition, as a side effect, the space saving and weight reduction of a connector body having a connector can be achieved, and costs can be reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a cross-sectional view schematically showing an example of a substrate.

[0020] Figure 2 It is a cross-sectional view schematically showing a state where a thermosetting connection material is provided on a terminal of a substrate.

[0021] Figure 3 It is a cross-sectional view schematically showing the alignment between the first terminal array of the substrate and the second terminal array of the connector.

[0022] Figure 4 It is a cross-sectional view schematically showing a state where the connector is pressed from the connector side by a tool.

[0023] Figure 5 It is a cross-sectional view schematically showing a state where the connector is fixed to the substrate.

[0024] Figure 6 It is a cross-sectional view schematically showing a state where a substrate and a connector are heated in a reflow furnace.

[0025] Figure 7 is a cross-sectional view schematically showing a connection body.

[0026] Figure 8 This is a cross-sectional view showing an example of the short dimension direction of the connector. DETAILED DESCRIPTION

[0027] Hereinafter, regarding the embodiments of the present technology, Figure 1 The following is a detailed description in the following order.

[0028] 1. A method for manufacturing a connector.

[0029] 2. Connector.

[0030] 3. Thermosetting connecting materials.

[0031] 4. Implementation examples.

[0032] <1. Method for manufacturing a connected body>

[0033] The manufacturing method of the connector in the present embodiment includes the following steps: fixing a connector on a first terminal row of a substrate via a thermosetting connection material containing solder particles, wherein the connector has a second terminal row with a minimum distance between terminals of 0.8 mm or less on the inner side of the bonding surface with the substrate; and joining the first terminal row and the second terminal row under no load using a reflow furnace set to a temperature above the melting point of the solder particles. Here, the ratio of the average particle size of the solder particles to the minimum distance between terminals in the first terminal row and the second terminal row is preferably less than 0.15, and more preferably less than 0.1.

[0034] In this specification, the average particle size is the average value of the major axis diameter of the particles measured, for example, at N=20 or more, preferably N=50 or more, and more preferably N=200 or more, in an observed image using an electron microscope such as a metal microscope, an optical microscope, or a SEM (Scanning Electron Microscope). When the particles are spherical, the average particle size is the average value of the diameters of the particles. In addition, it can also be a measured value measured using a known image analysis software ("WinROOF": Mitani Shoji (Strain), "A-Image-kun (registered trademark)": Asahi Kasei Engineering Co., Ltd., etc.) for the observed image, or a measured value (N=1000 or more) measured using an image-type particle size distribution measuring device (for example, FPIA-3000 (Malvern Company)). The average particle size obtained by the observed image or the image-type particle size distribution measuring device can be used as the average value of the maximum length of the particles. It should be noted that when making a thermosetting connecting material, the manufacturer's values ​​such as the particle size (D50) at which the frequency accumulation in the particle size distribution is 50% and the arithmetic mean diameter (preferably on a volume basis) obtained by a simple laser diffraction / scattering method can be used. In addition, a connector refers to two materials or components electrically connected. In addition, joining refers to connecting two materials or components together. No load refers to a state without mechanical pressure.

[0035] The substrate is not particularly limited as long as it has wiring, and can be a substrate broadly defined as a so-called printed circuit board (PWB) with electrodes that can carry connectors. It can be a rigid substrate or a flexible substrate (FPC). Examples of substrates based on the type of base material include, for example, glass substrates, ceramic substrates, plastic substrates, etc.

[0036] The connector has a second terminal row with a minimum distance between terminals of less than 0.8 mm, the second terminal row is formed at least on the inner side of the joint surface with the substrate, and the connector body overlaps with the first terminal row of the substrate. The minimum distance between the terminals may also be less than 0.35 mm. The first terminal row and the second terminal row (electrode arrangement, electrode group) provided on the substrate and the connector, respectively, are arranged opposite to each other, and the terminal row may also be provided on the substrate in a manner that multiple connectors are mounted on one substrate. That is, the substrate may be connected to multiple connectors at the same time.

[0037] In addition, the connector has a second terminal row on the inner side of the joint surface with the substrate, so that in the process of aligning and fixing the connector, a sufficient load can be applied in the vertical direction to make the solder particles contact with the terminals of the substrate and the terminals of the connector, and it becomes easy to remove the oxide film on the surface of the solder particles. The alignment mark can also be set in a manner corresponding to the connector and the substrate.

[0038] In addition, it is preferable that the surfaces of the terminals of the substrate and the terminals of the connector are plated with gold. It should be noted that the substrate and the connector preferably have heat resistance in the reflow process.

[0039] The connector in this embodiment is connected by solder particles widely used in BGA (Ball grid array) and the like, and has high connection reliability, so it can be used for various purposes such as sensor equipment, vehicle-mounted equipment, IoT (Internet of Things) equipment, etc. However, it is smaller than the solder particles used in BGA.

[0040] The thermosetting connection material can be any of a film-like thermosetting connection film or a paste-like thermosetting connection paste. In addition, the thermosetting connection paste can be made into a film-like shape during connection, or can be made into a form close to a film by mounting parts.

[0041] In the case of a thermosetting connection paste, as long as a specified amount can be evenly applied on the substrate, for example, coating methods such as dispensing, stamping, and screen printing can be used, and it can also be dried as needed. In this case, by using and modifying the equipment used for the solder paste in the past, it can be expected to suppress equipment investment. In the case of a thermosetting connection film, not only can the amount of bonding material (for example, anisotropic conductive bonding material) be uniformed according to the film thickness, but it can also be laminated to the substrate at the same time, which can shorten the production rhythm, so it is particularly preferred. In addition, it is easy to operate by being made into a film in advance, so it can be expected that the operating efficiency will also be improved. In this case, a film laminating device is introduced into the previous equipment, as described later, a bonding device according to the situation; or it can be improved to set it up, and the efficiency of the operation can be sought with minimal equipment investment.

[0042] Below, refer to Figure 1 to Figure 7 , the following steps are described: step (A), setting a thermosetting connecting material on the first terminal column of the substrate; step (B), fixing the connector on the thermosetting connecting material; and step (C), using a reflow furnace set to above the melting point of the solder particles, so that the first terminal column of the substrate and the second terminal column of the connector are joined.

[0043] [Step (A)]

[0044] Figure 1 is a cross-sectional view schematically showing an example of a substrate, Figure 2 2 is a cross-sectional view schematically showing a state where a thermosetting connection material is provided on a terminal of a substrate. Figure 1 and Figure 2 As shown, in step (A), a thermosetting connection material 20 containing solder particles 21 is provided on the first terminal array 11 of the substrate 10 .

[0045] Process (A) can be a process of forming a thermosetting connection paste into a film on a substrate, or it can be a temporary bonding process of bonding a thermosetting connection film to a substrate at low temperature and low pressure as used in conventional conductive films and anisotropic conductive films, or it can be a lamination process of laminating a thermosetting connection film onto a substrate.

[0046] When step (A) is a temporary lamination step, the thermosetting bonding film can be disposed on the substrate under known use conditions. In this case, only the previous device needs to be used to set and change the tool, thereby obtaining economic advantages.

[0047] When process (A) is a lamination process, for example, a pressurized laminator is used to laminate the thermosetting connection film onto the substrate. The lamination process can also be a vacuum pressurized type. If the conductive film or anisotropic conductive film is temporarily bonded using a heating and pressing tool, the width of the film is restricted by the width of the tool, but in the case of a lamination process, a heating and pressing tool is not used, so it can be expected that a wider width can be carried at the same time. In addition, a piece of thermosetting connection film can also be laminated to one substrate. Thus, the up and down movement of the heating and pressing tool and the conveying of the thermosetting connection film are not performed multiple times, so the time for setting the process of the thermosetting connection material can be shortened.

[0048] In step (A), the bonding material is arranged on the substrate, so the thickness of the thermosetting connection material is required to be within a specified range. As for the lower limit of the thickness of the thermosetting connection material, if the thickness is too thin, although it can be expected that the clamping of the solder particles between the electrodes becomes easy, the difficulty when it is made into a film may increase, and the technical difficulty when it is arranged on the substrate increases, so the lower limit of the thickness is more than 50% of the average particle size of the solder particles, preferably more than 80%, and more preferably more than 90%. In addition, the upper limit of the thickness of the thermosetting connection material is less than 300% of the average particle size of the solder particles, preferably less than 200%, and more preferably less than 150%. If the thickness of the thermosetting connection material is too thick, it may cause obstacles to the joining.

[0049] In addition, in consideration of the extrusion of the connector in the step (B) described later, from the viewpoint that it is preferably easy to remove the thermosetting connection material before clamping the solder particles, the upper limit of the ratio of the average particle size of the solder particles to the thickness of the thermosetting connection material is preferably 1.4 or less, more preferably 1.2 or less, and further preferably 1.0 or less. If the ratio of the average particle size of the solder particles to the thickness of the thermosetting connection material is large, high pressure is required during the extrusion of the connector in the step (B), which may damage the connector, and is therefore not preferred.

[0050] [Process (B)]

[0051] Figure 3 is a cross-sectional view schematically showing the alignment of the terminal array of the substrate and the terminal array of the connector, Figure 4 2 is a cross-sectional view schematically showing a state where the connector is squeezed from the connector side using a tool. Figure 3 and Figure 4 As shown, in step (B), the terminal array 11 of the substrate 10 is aligned with the terminal array 31 of the connector 30, and the connector 30 is fixed on the thermosetting connection material 20. In this technology, self-alignment based on solder cannot be expected, so it is ideal that in step (B), the substrate 10 is correctly aligned and fixed using the thermosetting connection material 20.

[0052] In step (B), the first terminal array 11 of the substrate 10 and the second terminal array 31 of the connector 30 are aligned using the tool 40, and the connector 30 is mounted on the thermosetting connection material 20. The tool 40 is preferably a heated pick-up tool, and preferably has a suction mechanism for sucking the connector 30.

[0053] Furthermore, in step (B), temporary crimping is preferably performed by squeezing from the connector 30 side using tool 40. The pressure for squeezing the connector 30 is greater than that in step (A), and is applied to the electrode area where the first terminal array of the substrate 10 and the second terminal array of the connector 30 face each other. The upper limit of the pressure is not particularly limited as long as it does not cause deformation of the connector body or mounted parts. In addition, the lower limit of the pressure may be, for example, greater than 1.0 MPa, greater than 2.0 MPa, greater than 3.0 MPa, or greater than 5.0 MPa. The purpose of temporary crimping is, for example, Figure 4 As shown, the solder particles 21 are reliably clamped between the electrodes of the first terminal column 11 of the substrate 10 and the second terminal column 31 of the connector 30, and heat is applied to preliminarily make the solder particles 21 a solder joint 24 in a molten state or a state close to the joint, which is advantageous for the joint between the electrodes accompanied by the melting of the solder particles during the reflow process. Thus, the oxide film on the surface of the solder particles can be removed. In addition, in temporary crimping, the first terminal column 11 of the substrate 10 can also be directly contacted with the second terminal column 31 of the connector 30, which relatively reduces the contribution of the solder particles in the joint in the reflow process, so that the conduction is stable and easy to obtain. By making the first terminal column of the substrate 10 directly contact the second terminal column of the connector 30, and there are solder particles near it, so that the solder particles become unloaded, and only melting during the reflow process helps the joint of the electrodes of the connector and the electrodes of the substrate, and the amount of solder particles that do not produce self-alignment is matched, so it is easy to achieve a fine pitch connection. Such temporary crimping and solder bonding using the reflow process are examples of how this technology differs from conventional solder paste or BGA-based connection methods. It should be noted that, based on the viewpoint that it is easy to follow the previous insights, the temporary crimping conditions for anisotropic connection can be the same. As the temporary crimping conditions commonly used in anisotropic connection, it is preferably below 2.0MPa, more preferably below 1.5MPa, and further preferably below 1.0MPa. In addition, the lower limit of the pressure is preferably above 0.2MPa, more preferably above 0.4MPa. Even under this condition, the purpose can be achieved by adjusting the conditions of the solder particles and the adhesive until no-load connection (reflow process). The upper and lower limits sometimes vary according to the specifications of the device, so as long as the thermosetting connection material 20 can be pushed to the contact of the opposing electrodes, or to the purpose of the solder particle size, it is not limited to the above numerical range.

[0054] In addition, in step (B), the connector is preferably extruded at a temperature in the range of -30°C to +60°C at which the minimum melt viscosity of the thermosetting connection material reaches a temperature, and more preferably, the connector is extruded at a temperature in the range of -10°C to +40°C at which the minimum melt viscosity of the thermosetting connection material reaches a temperature. Thus, since the melt viscosity of the thermosetting connection material is reduced, even if the pressure for extruding the connector is set low, a state in which the solder particles 21 are sandwiched between the first terminal row 11 of the substrate 10 and the second terminal row 31 of the connector 30 can be obtained. In addition, in step (B), as long as a state in which the solder particles 21 are sandwiched between the first terminal row 11 of the substrate 10 and the second terminal row 31 of the connector 30 is obtained, or a state in which the electrodes are in contact with each other through the molten solder or a part of the molten solder, the thermosetting connection material of the thermosetting resin layer 22 can begin to solidify, and the thermosetting connection material may be in a semi-solid state called the so-called B stage in which the thermosetting connection material is not completely solidified, or may be completely solidified. The reason is that curing can be completely completed during the reflow process, or the resin can be melted after curing to obtain the connection between the electrodes using solder particles under the weight of the connector (under no-load state). From the perspective of manufacturing management, it is also preferred to be able to perform these selectively.

[0055] Furthermore, in step (B), a buffer material may be used between the tool 40 and the connector 30. As the buffer material, polytetrafluoroethylene (PTFE), silicone rubber, etc. may be used. This can further suppress damage to the connector 30.

[0056] [Process (C)]

[0057] Figure 5 is a cross-sectional view schematically showing a state where a connector is fixed to a substrate, Figure 6 is a cross-sectional view schematically showing a state where a substrate and a connector are heated in a reflow oven, Figure 7 Schematically shows a cross-sectional view of the connector. Figure 5 to Figure 7 As shown, in step (C), the first terminal array 11 of the substrate 10 and the second terminals 31 of the connector 30 are bonded together using a reflow furnace set at a temperature equal to or higher than the melting point of the solder particles 21 .

[0058] The reflow oven can heat and bond without mechanical pressure, so it is possible to suppress damage to the substrate 10 and the connector 30. In addition, compared with the anisotropic conductive connection using a conventional heating and pressurizing tool, no unnecessary resin flow is generated, so the involvement of bubbles can also be suppressed. In addition, since it is unloaded, it is expected that the movement of the solder particles will be reduced, and the capture efficiency of the solder particles is high. It should be noted that the electrodes can also be in direct contact with each other, and the adhesive maintains this state. In addition, the solder particles near the electrodes connected to each other can also assist in this situation and play a role. The solder particles can be clamped between the electrodes, or after the electrodes are directly connected, the solder particles present in the periphery melt, which helps to join. Therefore, it is preferred that the content of the solder particles is not self-aligned. This is one of the differences between this technology and the conventional anisotropic conductive connection. That is, in the present technology, conduction can be achieved through solder particles that serve as conductive particles (a state that is the same as or close to anisotropic connection), electrodes can be in direct contact with each other and an adhesive can maintain this state for conduction (a state different from anisotropic connection), or solder particles present near the electrodes can assist in conduction and connection between the electrodes.

[0059] Examples of the reflow furnace include atmospheric pressure reflow, vacuum reflow, atmospheric pressure oven, and autoclave (pressure oven). Among them, vacuum reflow and autoclave that can discharge bubbles contained in the bonding portion are preferably used.

[0060] The lower limit of the peak temperature (maximum reaching temperature) in the reflow furnace is preferably above the temperature at which the solder particles melt and the temperature at which the thermosetting adhesive begins to solidify, preferably above 150°C, more preferably above 180°C, and further preferably above 200°C. In addition, the upper limit of the peak temperature in the reflow furnace is below 300°C, more preferably below 290°C, and further preferably below 280°C. Thus, the first terminal row 11 of the substrate 10 and the second terminal row 31 of the connector 30 are soldered 24. In addition, the content of the solder particles 21 in the thermosetting connection material is such that self-alignment cannot be expected, so many solder particles 21 are not integrated, and there are multiple solder joints 24 in one terminal. In addition, when the thermosetting connection material is a thermosetting adhesive, the multiple solder joints 24 in the terminal are bonded by a thermosetting adhesive. Here, solder bonding refers to melting the solder to connect the respective electrodes of the opposing electronic components.

[0061] In the reflow oven, the thermosetting resin is melted by heating, the solder particles 31 sandwiched between the electrodes are melted by formal heating above the melting point of the solder, the solder wets and spreads on the electrodes, and the first terminal row 11 of the substrate 10 is joined to the second terminal row 31 of the connector 30 by cooling. In addition to the heating process and the cooling process, the reflow process may also include a process of maintaining a certain temperature (holding process). There may be a peak process that reaches the highest temperature, and it may also include a process in the middle of heating or cooling. The heating process may be a process of melting the adhesive (for example, until 120°C); and a process of melting the solder particles and spreading the coating (for example, 120 to 175°C). Therefore, as an example, the heating rate may be 10 to 120°C / min, or 20 to 100°C / min. The holding time of the holding process (for example, 175 to 180°C) also becomes a process of curing the adhesive. As for the temperature, as an example, the temperature is 160 to 230°C, which may have a difference of about 5 to 10°C, or may be the same as the peak temperature. The time may be appropriately selected, for example, 0.5 min or more, 0.75 min or more, and if it is too long, the manufacturing efficiency deteriorates, so it is, for example, 5 min or less, 3 min or less. Reflow soldering may be only a heating process and a cooling process. In this case, as long as the curing resin is melted through the two processes, the solder particles 31 sandwiched between the electrodes are melted by the formal heating above the melting point of the solder, the solder wets and spreads on the electrodes, and the first terminal row 11 of the substrate 10 is connected to the second terminal row 31 of the connector 30 by cooling. In terms of process management, it can be managed for a time exceeding the specified temperature. The specified temperature is preferably 150°C, more preferably 180°C or more, and further preferably 200°C or more. The specified time is, for example, 0.5 min. By cooling through the cooling process (below the melting point of the solder particles), the solder particles can be made into a solid phase and connected between the electrodes. In order to improve productivity and remove quickly, a higher cooling rate is better. It is ideal not to quench the bonded state to improve the quality of the bonded body, so a lower cooling rate is better. As an example, it can be the same speed as the heating process, preferably 10 to 30 ° C / min. The cooling rate can be adjusted according to the combination of the bonding objects and the conditions of the adhesive used. It also affects the removal temperature and its environment.

[0062] According to the manufacturing method of the above-mentioned connector, by making the solder particles and the film thickness similar before the reflow process, the solder particles are brought into contact with the terminals, and the joining can be performed more easily. In addition, when the thermosetting connection material is a thermosetting adhesive, by combining the heating / maintenance / cooling of the reflow process with the thermosetting behavior of the thermosetting connection material, the resin melting in the reflow process, the clamping of the solder particles between the terminals, and the solder melting / resin solidification can be optimized. It should be noted that the thermosetting behavior of the thermosetting connection material can be determined by DSC and the viscosity measurement using a rheometer.

[0063] In addition, the manufacturing device of the connector includes: a material setting unit for setting a thermosetting connection material containing solder particles on the first terminal column of the substrate; a fixing unit for fixing the connector on the thermosetting connection material; and a reflow furnace for joining the first terminal column of the substrate and the second terminal column of the connector.

[0064] When the thermosetting connection material is a film, the material setting part can be a temporary bonding device that bonds the film to the substrate at low temperature and low pressure, or a laminating device that laminates the film to the substrate. In addition, when the thermosetting connection material is a paste, the material setting part can also be a coating device that uniformly applies a specified amount on the substrate. As for the fixing part, for example, a flip chip bonder with a heating mechanism and a pressurizing mechanism can be used, and a tool is used to adsorb the connector and align it, and the tool is pressed down to fix the connector on the thermosetting connection material. The device used in the connector connection in the past can also be used for alignment and fixing. The reflow furnace is set to a maximum temperature above the melting point of the solder particles, and the connector is heated while it is fixed to the substrate, so that the terminals of the substrate are joined with the terminals of the connector.

[0065] <2. Connector>

[0066] Figure 7 Schematically shows a cross-sectional view of the connector. Figure 7 As shown, the connector of this embodiment comprises: a substrate 10 having a first terminal row 11; a connector 30 having a second terminal row 31; and an adhesive layer 23, which uses solder particles 21 to solder the first terminal row 11 and the second terminal row 31 together 24, and adheres the substrate 10 to the second connector 30.

[0067] In addition, the upper limit of the minimum value of the distance between adjacent terminals in the first terminal column 11 and the second terminal column 31 (space distance) is less than 0.8 mm, preferably less than 0.3 mm, and more preferably less than 0.2 mm. In addition, the lower limit of the minimum value of the distance between adjacent terminals in the first terminal column 11 and the second terminal column 31 is more than 50 μm, more preferably more than 60 μm, and further preferably more than 70 μm.

[0068] The upper limit of the ratio of the average particle size of the solder particles 21 to the minimum value of the distance between adjacent terminals (distance between gaps) in the first terminal array 11 and the second terminal array 31 is less than 0.15, and more preferably 0.1 or less.

[0069] Based on the relationship between the distance between adjacent terminals in the first terminal array 11 and the second terminal array 31 and the average particle size of the solder particles 21 as described above, the first terminal array 11 of the substrate 10 and the second terminal array 31 of the connector 30 can be joined using a reflow furnace.

[0070] The substrate 10 is similar to the above, and as examples of substrates based on the type of substrate, for example, rigid substrates, glass substrates, ceramic substrates, plastic substrates, etc. can be cited. In addition, from the viewpoint of economy, it is preferred that no short-circuit prevention processing (walls, grooves, etc.) for solder resist is formed between adjacent terminals of the first terminal column. That is, the height between adjacent terminals of the first terminal column 11 is preferably 100 μm or less, more preferably 35 μm or less, and further preferably 12 μm or less. In addition, the lower limit of the height between adjacent terminals of the first terminal column 11 can be the same as the terminal height (the terminals are horizontally the same as the substrate surface, the terminals are not raised, and the connection surface of the substrate is flat), or the terminals of the first terminal column provided on the substrate protrude more than the substrate plane. Thus, in step (B), the solder particles 21 are clamped between the first terminal column 11 of the substrate 10 and the second terminal column 31 of the connector 30 in a state of contacting the solder particles 21.

[0071] The adhesive layer 23 is a film-like adhesive layer formed by curing the thermosetting connection material of the thermosetting resin layer 22 after step (C), and the first terminal array 11 of the substrate 10 and the second terminal array 31 of the connector 30 are soldered 34, and the thermosetting connection material is filled between the substrate 10 and the connector 30. In addition, there are multiple solder joints 24 in one terminal, and when the thermosetting connection material is a thermosetting adhesive, in addition to the multiple solder joints 24, there are also bonding sites using the thermosetting adhesive.

[0072] In this specification, the connector refers to a main resin molded product with a fitting portion. The fitting portion fits the terminal and plug of the FPC, for example, and the spacing of the fitting terminals is less than 0.8 mm, preferably less than 0.3 mm, and more preferably less than 0.2 mm. It refers to a connector that can electrically connect and mechanically combine the part inserted into the fitting portion with the part installed with the connector. For example, there are connectors in which multiple electrodes protrude in the long dimension direction in the resin molded product (so-called centipede-shaped connectors), and connectors that do not protrude (flip chip-type connectors). Even for connectors with narrow spacing, the connector can be fixed under low pressure as described above, and heated and joined under no load using a reflow oven.

[0073] Figure 8 : is a cross-sectional view showing an example of the short dimension direction of the connector. The connector is a vertical fitting type, and is composed of a receptacle and a plug. The receptacle is fixed with a first terminal 52A and a second terminal 52B by means of an insulating resin 51, and the plug is fixed with a first terminal 54A and a second terminal 54B by means of an insulating resin 53. In addition, in the long dimension direction of the connector, the first terminal 52A and the second terminal 52B and the first terminal 54A and the second terminal 54B are formed at a predetermined pitch. In this connector, for example, the first terminal 52A or the second terminal 52B of the receptacle is equivalent to Figure 3 The second terminal array 31 of the connector 30 is shown in cross section in the longitudinal direction.

[0074] The insulating resins 51 and 53 are made of, for example, polyamide, LCP (Liquid Crystal Polymer), or the like, and fix the first terminal 52A and the second terminal 52B and the first terminal 54A and the second terminal 54B by, for example, resin molding.

[0075] The first terminal 52A and the second terminal 52B and the first terminal 54A and the second terminal 54B are bent so that the first terminals 52A and 54A and the second terminals 52B and 54B are vertically interlocked. In addition, wires are formed at the ends of the short dimension direction of the plug hole and the plug, respectively, to form a centipede-shaped terminal.

[0076] In this embodiment, the connector can be fixed under low pressure, and a reflow oven is used to heat and bond without mechanical pressure, so even if the connector is a narrow-pitch connector, it can be installed. In addition, according to this embodiment, no leads are required, so it can be installed on a flip-chip connector having a second terminal row on the inner side of the bonding surface with the substrate, which can reduce the installation area. Compared with the conventional FPC, IC chip, etc. used for anisotropic conductive connection, the connector to which this technology is applied has a thickness in the connection direction (for inserting FPC, etc.). Therefore, compared with the conventional anisotropic connection, it may be easy to produce an alignment offset (referring to the relative offset of the first terminal arrangement and the second terminal arrangement) caused by the pressure (extrusion) during the connection. However, as long as temporary fixing is performed after alignment as described above, and heating and bonding is performed without mechanical pressure using a reflow oven under no load, such technical problems can be avoided. In other words, based on such reasons, this technology is also needed.

[0077] <3. Thermosetting connecting materials>

[0078] The thermosetting connection material in this embodiment is formed by dispersing solder particles in a thermosetting adhesive, and the content of the solder particles is 50wt% or less. Thus, the connector on the thermosetting connection material can be fixed and reflow soldering can be performed, and the self-alignment of the solder particles can be suppressed, so that a connector with a terminal array with a pitch of less than 0.8mm can be installed.

[0079] The lower limit of the mass ratio range of the amount of solder particles is preferably 20wt% or more, more preferably 30wt% or more, and more preferably 35wt% or more. The upper limit of the mass ratio range of the amount of solder particles is 50wt% or less, more preferably 45wt% or less, and more preferably 40wt% or less. In addition, the lower limit of the volume ratio range of the amount of solder particles is preferably 5vol% or more, more preferably 10vol% or more, and more preferably 15vol% or more. The upper limit of the volume ratio range of the amount of solder particles is preferably 30vol% or less, more preferably 25vol% or less, and more preferably 20vol% or less. By satisfying the above-mentioned mass ratio range or volume ratio range of the amount of solder particles, excellent conductivity, heat dissipation, and adhesion can be obtained. In the case where the solder particles are present in the adhesive, the volume ratio can be used. In the case of manufacturing an anisotropic conductive bonding material (the solder particles are present before the adhesive), the mass ratio can be used. The mass ratio can be converted into a volume ratio according to the specific gravity of the mixture, the mixing ratio, etc. If the amount of solder particles added is too small, excellent conductivity, heat dissipation, and adhesion cannot be obtained, while if the amount is too large, anisotropy is easily lost and excellent conduction reliability is difficult to obtain.

[0080] In addition, the thermosetting connection material preferably has an exothermic peak temperature higher than the melting point of the solder particles, and preferably has a melting temperature lower than the melting point of the solder particles. Here, the exothermic peak temperature can be measured using a rotational rheometer (manufactured by Thermo Fisher) under the conditions of measuring pressure 1N, temperature range 30-200°C, heating rate 10°C / min, measuring frequency 1Hz, and measuring plate diameter 8mm. Thus, the thermosetting adhesive is melted by heating, and the solder melts when the solder particles are clamped between the terminals, so that electronic parts with electrodes with small spacing can be joined.

[0081] When the thermosetting connecting material is in the form of a film as described above, the lower limit of the ratio of the average particle size of the solder particles to the thickness of the thermosetting connecting material is preferably 0.6 or more, more preferably 0.8 or more, and further preferably 0.9 or more. When the ratio of the average particle size of the solder particles to the thickness of the thermosetting connecting material is large, in step (B), the solder particles are easily clamped between the electrodes, but the difficulty of operability may increase when the film is formed.

[0082] In addition, the upper limit of the ratio of the average particle size of the solder particles to the thickness of the thermosetting connection material is preferably 1.5 or less, more preferably 1.2 or less, and further preferably 1.1 or less. When the ratio of the average particle size of the solder particles to the thickness of the thermosetting connection material is large, high pressure is required in the extrusion of the connector in step (B), which may damage the connector.

[0083] The film thickness can be measured using a known micrometer or digital thickness gauge (e.g., Mitutoyo Co., Ltd.: MDE-25M, minimum display 0.0001mm) that can measure less than 1 μm, preferably less than 0.1 μm. The film thickness can be determined by measuring at least 10 locations and averaging. However, when the film thickness is thinner than the particle size, a contact thickness gauge is not suitable, so it is preferred to use a laser displacement meter (e.g., KEYENCE Co., Ltd., spectral interference displacement type SI-T series, etc.). Here, the film thickness refers to the thickness of the resin layer only, excluding the particle size.

[0084] [Thermosetting adhesive]

[0085] As thermosetting adhesives (insulating adhesives), there can be listed: thermal free radical polymerization resin compositions comprising (meth)acrylate compounds and thermal free radical polymerization initiators, thermal cationic polymerization resin compositions comprising epoxy compounds and thermal cationic polymerization initiators, thermal anionic polymerization resin compositions comprising epoxy compounds and thermal anionic polymerization initiators, etc. In addition, known adhesive compositions can also be used. It should be noted that the (meth)acrylic monomer refers to any of acrylic monomers and methacrylic monomers.

[0086] In the following, as a specific example, a thermal anionic polymerization type resin composition containing a solid epoxy resin, a liquid epoxy resin, and an epoxy resin curing agent is given as an example for description.

[0087] Solid epoxy resin is solid at room temperature, and there is no particular limitation as long as it has one or more epoxy groups in the molecule, and for example, it can be bisphenol A type epoxy resin, biphenyl type epoxy resin, etc. Thus, the film shape can be maintained. It should be noted that room temperature refers to the range of 20°C ± 15°C (5°C to 35°C) specified in JIS Z 8703.

[0088] The liquid epoxy resin is not particularly limited as long as it is liquid at room temperature, and may be, for example, a bisphenol A epoxy resin, a bisphenol F epoxy resin, or a urethane-modified epoxy resin.

[0089] The amount of the liquid epoxy resin is preferably 160 parts by mass or less, more preferably 100 parts by mass or less, and even more preferably 70 parts by mass or less, based on 100 parts by mass of the solid epoxy resin. If the amount of the liquid epoxy resin is increased, it becomes difficult to maintain the film shape.

[0090] The epoxy resin curing agent is not particularly limited as long as it is a heat curing agent that starts curing due to heat, and examples thereof include anionic curing agents such as amines and imidazoles, and cationic curing agents such as sulfonium salts. In addition, the curing agent may be microencapsulated to obtain resistance to solvents used in film formation.

[0091] Furthermore, the thermosetting adhesive preferably does not contain a flux compound, thereby improving the insulation property, eliminating the need for a flux compound cleaning step, and shortening the time required for an oxide film removal step in a reflow process.

[0092] [Solder particles]

[0093] The solder particles are preferably dispersed in the thermosetting connection material, and the solder particles may be arranged randomly or in a certain pattern. The average particle size can be determined by using a known metal microscope or optical microscope to randomly select 5 or more locations with a diameter of 1 mm when viewed from above the film. 2 Please confirm the above area.

[0094] In addition, the solder particles may be aggregates formed by agglomeration of a plurality of particles. The average particle size of the solder particles in each aggregate can be measured in the same manner as the above-mentioned average particle size.

[0095] The average particle size of the solder particles is preferably less than 0.2 times the minimum value of the distance between terminals (space distance) in the first terminal column of the substrate and the second terminal column of the connector. If the average particle size of the solder particles is greater than 0.2 times the minimum value of the distance between terminals in the first terminal column of the substrate and the second terminal column of the connector, the possibility of short circuit becomes higher.

[0096] The lower limit of the average particle size of the solder particles is preferably 0.5 μm or more, more preferably 3 μm or more, and more preferably 5 μm or more. Thus, the coating thickness of the film can be constant. If the average particle size of the solder particles is less than 0.5 μm, a good solder joint state with the electrode portion cannot be obtained, and there is a tendency for reliability to deteriorate. In addition, the upper limit of the average particle size of the solder particles can be 50 μm or less, 30 μm or less, preferably 20 μm or less, and more preferably 10 μm or less. In addition, in the case of an agglomerate formed by agglomeration of multiple solder particles, the size of the agglomerate can also be equal to the average particle size of the above-mentioned solder particles. In the case of making an agglomerate, the average particle size of the solder particles can also be less than the above-mentioned value. The size of each solder particle can be obtained by electron microscope observation as described above.

[0097] In addition, the maximum diameter of the solder particles can be set to less than 200% of the average particle size, preferably less than 150% of the average particle size, and more preferably less than 120% of the average particle size. By making the maximum diameter of the solder particles within the above range, the solder particles can be clamped between the electrodes, and the electrodes can be joined by melting the solder particles. In addition, in the case of an agglomerate formed by agglomeration of multiple solder particles, the size of the agglomerate can be made equal to the maximum diameter of the above-mentioned solder particles. In the case of making an agglomerate, the maximum diameter of the solder particles can be made smaller than the above-mentioned value. The size of each solder particle can be obtained by electron microscope observation as described above.

[0098] The solder particles can be appropriately selected from Sn-Pb, Pb-Sn-Sb, Sn-Sb, Sn-Pb-Bi, Bi-Sn, Sn-Cu, Sn-Pb-Cu, Sn-In, Sn-Ag, Sn-Pb-Ag, Pb-Ag, etc. specified in JIS Z 3282-1999, depending on the electrode material, connection conditions, etc. The lower limit of the melting point of the solder particles is preferably 110°C or more, more preferably 120°C or more, and further preferably 130°C or more. The upper limit of the melting point of the solder particles can be 200°C or less, preferably 180°C or less, more preferably 160°C or less, and further preferably 150°C or less. In addition, for the solder particles, the flux compound can also be directly bonded to the surface for the purpose of activating the surface. The metal bonding with the electrode portion can be promoted by activating the surface.

[0099] [Other additives]

[0100] In addition to the above-mentioned insulating adhesive and solder particles, various additives used in conventional heat-curing adhesives can be added to the thermosetting connection material within the range that does not impair the effect of the present invention. The particle size of the additive is preferably smaller than the average particle size of the solder particles, but there is no particular limitation as long as it is a size that does not hinder the bonding between the electrodes.

[0101] The above-mentioned thermosetting connection material can be obtained by, for example, mixing an insulating adhesive and solder particles in a solvent, applying the mixture to a peeling treatment film in a manner of a specified thickness using a scraper coater, and drying to volatilize the solvent. In addition, the mixture can also be applied to a peeling treatment film using a scraper coater and then pressed to a specified thickness. In addition, in order to improve the dispersibility of the solder particles, high shear is preferably applied in a state containing a solvent. For example, a known intermittent planetary stirring device can be used. In addition, the residual solvent content of the thermosetting connection material is preferably less than 2%, more preferably less than 1%.

[0102] Example

[0103] <4. Example>

[0104] In this example, an adhesive film containing solder particles was prepared and used as a connector substitute to mount a flexible printed circuit board on a rigid substrate. Then, the insulation evaluation and connection resistance value evaluation of the mounted body were performed. It should be noted that this example is not limited to this.

[0105] [Insulation evaluation of the installation body]

[0106] For the mounted body sample, the resistance value between adjacent terminals was measured and 10 6 The number of Ω or less was counted as a short circuit. The evaluation of the mounted body without short circuit was evaluated as "OK", and the evaluation of the mounted body with one or more short circuits was evaluated as "NG".

[0107] [Evaluation of connection resistance value of mounted body]

[0108] The resistance of the mounted body samples when a current of 1 mA flowed between the terminals of the flexible printed circuit board and the rigid board was measured, and the median value was calculated. The mounted bodies with a median resistance value of 0.1Ω or less were evaluated as "OK", and the other mounted bodies were evaluated as "NG".

[0109] <Installation Example 1-1>

[0110] A flexible printed circuit board (FPC for evaluation produced by Dexerials Co., Ltd., terminal width 100 μm, distance between adjacent terminals (minimum value) 100 μm, line width / line spacing (line and space) 1:1, pitch 200 μm, number of terminals 30, Ni-Au plating) and a rigid substrate (rigid substrate for evaluation produced by Dexerials Co., Ltd., terminal width 100 μm, distance between adjacent terminals (minimum value) 100 μm, pitch 200 μm, number of terminals 30, 18 μm thick Cu pattern, Ni-Au plating) were prepared.

[0111] Under the loading conditions of 90℃-2s-1MPa, the flexible printed circuit board was aligned and fixed on the rigid substrate via an adhesive film. The adhesive film used was a 12μm thick adhesive film made of 38wt% of solder particles with an average particle size of 10μm (MP-L20, Senju Metal Industry Co., Ltd., Sn-58Bi alloy, solidification point temperature 139℃) in an acrylic thermosetting adhesive (Dexerials Co., Ltd., minimum melt viscosity reaching temperature 80℃).

[0112] Then, the flexible printed circuit board was mounted on the rigid substrate by reflow soldering. The reflow soldering conditions were 150°C to 260°C-100 sec, and the peak temperature was 260°C.

[0113] Table 1 shows the results of the insulation evaluation and the connection resistance value evaluation of the mounted body.

[0114] <Installation example 1-2>

[0115] As shown in Table 1, a mounted body was produced in the same manner as in Mounting Example 1-1 except that the mounting conditions were set to 100° C.-2 s-1 MPa, and the insulation evaluation and connection resistance value evaluation of the mounted body were performed.

[0116] <Installation examples 1-3>

[0117] As shown in Table 1, a mounted body was produced in the same manner as in Mounting Example 1-1 except that the mounting conditions were set to 130° C.-2 s-1 MPa, and insulation evaluation and connection resistance value evaluation of the mounted body were performed.

[0118] <Installation examples 1-4>

[0119] As shown in Table 1, a mounted body was produced in the same manner as in Mounting Example 1-1 except that the mounting conditions were set to 150° C.-2 s-1 MPa, and insulation evaluation and connection resistance value evaluation of the mounted body were performed.

[0120] <Installation Example 2-1>

[0121] A flexible printed circuit board (FPC for evaluation produced by Dexerials Co., Ltd., terminal width 300 μm, distance between adjacent terminals (minimum value) 300 μm, line width / line spacing 1:1, pitch 300 μm, number of terminals 30, Ni-Au plating) and a rigid substrate (rigid substrate for evaluation produced by Dexerials Co., Ltd., terminal width 300 μm, distance between adjacent terminals (minimum value) 300 μm, pitch 300 μm, number of terminals 30, 18 μm thick Cu pattern, Ni-Au plating) were prepared.

[0122] Under the loading conditions of 90℃-2s-1MPa, the flexible printed circuit board was aligned and fixed on the rigid substrate via an adhesive film. The adhesive film used was a 35μm thick adhesive film made of 38wt% solder particles with an average particle size of 30μm (MP-L20, Senju Metal Industry Co., Ltd., Sn-58Bi alloy, solid phase point temperature 139℃) in an acrylic thermosetting adhesive (Dexerials Co., Ltd., minimum melt viscosity reaching temperature 80℃).

[0123] Then, the flexible printed circuit board was mounted on the rigid substrate by reflow soldering. The reflow soldering conditions were 150°C to 260°C-100 sec, and the peak temperature was 260°C.

[0124] Table 1 shows the results of the insulation evaluation and the connection resistance value evaluation of the mounted body.

[0125] <Installation Example 2-2>

[0126] As shown in Table 1, a mounted body was produced in the same manner as in Mounting Example 2-1 except that the mounting conditions were set to 100° C.-2 s-1 MPa, and the insulation evaluation and connection resistance value evaluation of the mounted body were performed.

[0127] <Installation example 2-3>

[0128] As shown in Table 1, a mounted body was produced in the same manner as in Mounting Example 2-1 except that the mounting conditions were set to 130° C.-2 s-1 MPa, and insulation evaluation and connection resistance value evaluation of the mounted body were performed.

[0129] <Installation example 2-4>

[0130] As shown in Table 1, a mounted body was produced in the same manner as in Mounting Example 2-1 except that the mounting conditions were set to 150° C.-2 s-1 MPa, and insulation evaluation and connection resistance value evaluation of the mounted body were performed.

[0131] <Installation Example 3-1>

[0132] A flexible printed circuit board (FPC for evaluation produced by Dexerials Co., Ltd., terminal width 100 μm, distance between adjacent terminals (minimum value) 100 μm, line width / line spacing 1:1, pitch 100 μm, number of terminals 30, Ni-Au plating) and a rigid substrate (rigid substrate for evaluation produced by Dexerials Co., Ltd., terminal width 100 μm, distance between adjacent terminals (minimum value) 100 μm, pitch 100 μm, number of terminals 30, 18 μm thick Cu pattern, Ni-Au plating) were prepared.

[0133] Under the loading conditions of 90℃-2s-1MPa, the flexible printed circuit board was aligned and fixed on the rigid substrate via an adhesive film. The adhesive film used was a 28μm thick adhesive film made of 38wt% solder particles with an average particle size of 30μm (MP-L20, Senju Metal Industry Co., Ltd., Sn-58Bi alloy, solid phase point temperature 139℃) in an acrylic thermosetting adhesive (Dexerials Co., Ltd., minimum melt viscosity reaching temperature 80℃).

[0134] Then, the flexible printed circuit board was mounted on the rigid substrate by reflow soldering. The reflow soldering conditions were 150°C to 260°C-100 sec, and the peak temperature was 260°C.

[0135] Table 1 shows the results of the insulation evaluation and the connection resistance value evaluation of the mounted body.

[0136] <Installation Example 3-2>

[0137] As shown in Table 1, a mounted body was produced in the same manner as in Mounting Example 3-1 except that the mounting conditions were set to 100° C.-2 s-1 MPa, and the insulation evaluation and connection resistance value evaluation of the mounted body were performed.

[0138] <Installation Example 3-3>

[0139] As shown in Table 1, a mounted body was produced in the same manner as in Mounting Example 3-1 except that the mounting conditions were set to 130° C.-2 s-1 MPa, and insulation evaluation and connection resistance value evaluation of the mounted body were performed.

[0140] <Installation example 3-4>

[0141] As shown in Table 1, a mounted body was produced in the same manner as in Mounting Example 3-1 except that the mounting conditions were set to 150° C.-2 s-1 MPa, and insulation evaluation and connection resistance value evaluation of the mounted body were performed.

[0142] <Installation Example 4-1>

[0143] A flexible printed circuit board (FPC for evaluation produced by Dexerials Co., Ltd., terminal width 100 μm, distance between adjacent terminals (minimum value) 100 μm, line width / line spacing 1:1, pitch 100 μm, number of terminals 30, Ni-Au plating) and a rigid substrate (rigid substrate for evaluation produced by Dexerials Co., Ltd., terminal width 100 μm, distance between adjacent terminals (minimum value) 100 μm, pitch 100 μm, number of terminals 30, 18 μm thick Cu pattern, Ni-Au plating) were prepared.

[0144] Under the loading conditions of 90℃-2s-1MPa, the flexible printed circuit board was aligned and fixed on the rigid substrate via an adhesive film. The adhesive film used was a 35μm thick adhesive film made of 38wt% solder particles with an average particle size of 30μm (MP-L20, Senju Metal Industry Co., Ltd., Sn-58Bi alloy, solid phase point temperature 139℃) in an acrylic thermosetting adhesive (Dexerials Co., Ltd., minimum melt viscosity reaching temperature 80℃).

[0145] Then, the flexible printed circuit board was mounted on the rigid substrate by reflow soldering. The reflow soldering conditions were 150°C to 260°C-100 sec, and the peak temperature was 260°C.

[0146] Table 2 shows the results of the insulation evaluation and the connection resistance value evaluation of the mounted body.

[0147] <Installation Example 4-2>

[0148] As shown in Table 2, a mounted body was produced in the same manner as in Mounting Example 4-1 except that the mounting conditions were set to 100° C.-2 s-1 MPa, and the insulation evaluation and connection resistance value evaluation of the mounted body were performed.

[0149] <Installation Example 4-3>

[0150] As shown in Table 2, a mounted body was produced in the same manner as in Mounting Example 4-1 except that the mounting conditions were set to 130° C.-2 s-1 MPa, and the insulation evaluation and connection resistance value evaluation of the mounted body were performed.

[0151] <Installation Example 4-4>

[0152] As shown in Table 2, a mounted body was produced in the same manner as in Mounting Example 4-1 except that the mounting conditions were set to 150° C.-2 s-1 MPa, and the insulation evaluation and connection resistance value evaluation of the mounted body were performed.

[0153] <Installation Example 5-1>

[0154] A flexible printed circuit board (FPC for evaluation produced by Dexerials Co., Ltd., terminal width 200 μm, distance between adjacent terminals (minimum value) 200 μm, line width / line spacing 1:1, pitch 200 μm, number of terminals 30, Ni-Au plating) and a rigid substrate (rigid substrate for evaluation produced by Dexerials Co., Ltd., terminal width 200 μm, distance between adjacent terminals (minimum value) 200 μm, pitch 200 μm, number of terminals 30, 18 μm thick Cu pattern, Ni-Au plating) were prepared.

[0155] Under the loading conditions of 90℃-2s-1MPa, the flexible printed circuit board was aligned and fixed on the rigid substrate via an adhesive film. The adhesive film used was a 35μm thick adhesive film made of 38wt% solder particles with an average particle size of 30μm (MP-L20, Senju Metal Industry Co., Ltd., Sn-58Bi alloy, solid phase point temperature 139℃) in an acrylic thermosetting adhesive (Dexerials Co., Ltd., minimum melt viscosity reaching temperature 80℃).

[0156] Then, the flexible printed circuit board was mounted on the rigid substrate by reflow soldering. The reflow soldering conditions were 150°C to 260°C-100 sec, and the peak temperature was 260°C.

[0157] Table 2 shows the results of the insulation evaluation and the connection resistance value evaluation of the mounted body.

[0158] <Installation Example 5-2>

[0159] As shown in Table 2, a mounted body was produced in the same manner as in Mounting Example 5-1 except that the mounting conditions were set to 100° C.-2 s-1 MPa, and the insulation evaluation and connection resistance value evaluation of the mounted body were performed.

[0160] <Installation Example 5-3>

[0161] As shown in Table 2, a mounted body was produced in the same manner as in Mounting Example 5-1 except that the mounting conditions were set to 130° C.-2 s-1 MPa, and insulation evaluation and connection resistance value evaluation of the mounted body were performed.

[0162] <Installation Example 5-4>

[0163] As shown in Table 2, a mounted body was produced in the same manner as in Mounting Example 5-1 except that the mounting conditions were set to 150° C.-2 s-1 MPa, and insulation evaluation and connection resistance value evaluation of the mounted body were performed.

[0164] [Table 1]

[0165]

[0166] [Table 2]

[0167]

[0168] According to Mounting Examples 1-2 to 1-4 and Mounting Examples 2-2 to 2-4, by setting the minimum distance between adjacent terminals to 0.3 mm or less and the ratio of the average particle size of the solder particles to the minimum distance between adjacent terminals to less than 0.15, a mounting body having excellent insulation and conductivity can be obtained. In addition, by setting the temperature during alignment to 100°C to 150°C for an adhesive film having a minimum melt viscosity reaching temperature of 80°C, a mounting body having excellent insulation and conductivity can be obtained.

[0169] It should be noted that in this embodiment, a flexible printed circuit board is installed, and a connector can also be installed. In addition, the connector can be installed not only in a centipede type but also in a flip-chip type.

[0170] Description of Reference Numerals

[0171] 10: substrate; 11: first terminal array; 20: thermosetting connection material; 21: solder particles; 30: connector; 31: second terminal array; 40: tool; 51: insulating resin; 52A: first terminal; 52B: second terminal; 53: insulating resin; 54A: first terminal; 54B: second terminal.

Claims

1. A method for manufacturing a connector, comprising the following steps: A connector is fixed to the first terminal array of the substrate via a thermosetting connection material containing solder particles, wherein the connector has a second terminal array with a minimum distance between terminals of 0.8 mm or less on the inner side of the bonding surface with the substrate; and The first terminal array and the second terminal array are bonded to each other under no load using a reflow furnace set to a temperature higher than the melting point of the solder particles. The ratio of the average particle size of the solder particles to the minimum value of the distance between the terminals in the first terminal column and the second terminal column is less than 0.15, A ratio of an average particle size of solder particles to a thickness of the thermosetting connection material is 0.33 or more and 2.0 or less.

2. The method for manufacturing a connected body according to claim 1, wherein: A ratio of an average particle size of the solder particles to a minimum value of a distance between terminals in the first terminal array and the second terminal array is 0.1 or less.

3. The method for manufacturing a connected body according to claim 1 or 2, wherein: In the step of fixing the connector, the connector is crimped at a temperature in the range of -10°C to +40°C at which the thermosetting connection material reaches its lowest melt viscosity.

4. The method for producing a connected body according to any one of claims 1 to 3, wherein: In the step of fixing the connector, the connector is crimped at a pressure of 2.0 MPa or less.

5. The method for producing a connected body according to any one of claims 1 to 4, wherein: The connector is a resin molded product.

6. The method for manufacturing a connected body according to any one of claims 1 to 5, wherein: The content of the solder particles in the thermosetting connection material is 50 wt % or less.

7. The method for manufacturing a connected body according to any one of claims 1 to 6, wherein: The thermosetting connecting material is in film form.

8. A connector, comprising: A substrate having a first terminal array; A connector having a second terminal row with a minimum distance between terminals of 0.8 mm or less on the inner side of the bonding surface with the substrate; and an adhesive layer for bonding the first terminal array and the second terminal array with solder particles and bonding the substrate and the connector together, The ratio of the average particle size of the solder particles to the minimum value of the distance between the terminals in the first terminal column and the second terminal column is less than 0.15, The ratio of the average particle size of the solder particles to the thickness of the adhesive layer is 0.33 or more and 2.0 or less.

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