JP2021153049A - Connection body and manufacturing method thereof - Google Patents

Abstract

To provide a connection body and a manufacturing method thereof that can be made fine pitch and miniaturized.SOLUTION: A connection body includes a substrate 10 having a first terminal row 11, a connector 20 having second terminal rows 21A to 21E, and an adhesive layer 30 on which a thermosetting connection material that connects the first terminal row 11 and the second terminal rows 21 is cured, and the second terminal rows 21A to 21E are arranged on the bottom surface of the connector 20 to form a step absorbing portion that absorbs the step on the bottom surface, and the thermosetting connection material includes solder particles and a flux component. As a result, the first terminal row 11 and the second terminal rows 21A to 21E can be connected, such that the terminal row can be made a fine pitch and the connection body can be miniaturized.SELECTED DRAWING: Figure 1

Description

The present technology relates to a connector on which a connector is mounted and a method for manufacturing the connector.

Conventionally, in the mounting of a connector, solder paste is provided on a substrate, or solder (BGA) is provided on a lead wire portion of the connector, and solder mounting is performed by reflow (see, for example, Patent Document 1). In recent years, due to the demand for miniaturization of electronic devices, those having a connector pitch of 0.8 mm or less and further 0.3 mm or less are desired.

Anisotropic connection can be mentioned as a technique for connecting narrow-pitch terminal rows. However, since the connector is generally a resin molded product, when anisotropic connection is performed, the tool is pressed during the main crimping. This causes the connector to be deformed, and there is a concern that the cable cannot be inserted, for example.

Further, in the conventional solder mounting of the connector, since a solder resist is used for the terminal row on the substrate side, it is difficult to further narrow the pitch of the terminal row of the connector. Further, in the conventional connector, since the lead terminal (gull wing terminal) extends outward, the mounting area becomes large, which hinders the miniaturization of the mounting body.

Japanese Unexamined Patent Publication No. 10-284199

The present technology has been proposed in view of such conventional circumstances, and provides a connecting body capable of fine pitching and miniaturization, and a method for manufacturing the connecting body.

The connector according to the present technology is a thermosetting connection material that connects a substrate having a first terminal row, a connector having a second terminal row, and the first terminal row and the second terminal row. The second terminal row is arranged on the bottom surface of the connector to form a step absorbing portion that absorbs the step on the bottom surface, and the thermosetting connecting material is formed with solder particles. Contains a flux component.

In the method for manufacturing a connector according to the present technology, a second terminal row is arranged on the bottom surface of a substrate having a first terminal row via a thermosetting connecting material containing solder particles and a flux component. A connector having a step absorbing portion for absorbing the step on the bottom surface is placed, and the thermosetting connection material is thermoset at a temperature equal to or higher than the melting point of the solder particles without pressing the connector. The first terminal row and the second terminal row are connected.

According to the present technology, by arranging the terminal row on the bottom surface of the connector and absorbing the step on the bottom surface, the terminal row can be made a fine pitch and the connector can be miniaturized.

FIG. 1 is a cross-sectional view schematically showing an example of a connecting body according to the present embodiment. FIG. 2 is a top view showing an example of a plug according to the prior art. FIG. 3 is a top view showing an example of a receptacle according to the prior art. FIG. 4 is a cross-sectional view taken along the line AA of the plug shown in FIG. 2 and the receptacle shown in FIG. FIG. 5 is a top view showing an example of the plug according to the present embodiment. FIG. 6 is a top view showing an example of the receptacle according to the present embodiment. FIG. 7 is a cross-sectional view taken along the line AA of the plug shown in FIG. 5 and the receptacle shown in FIG. FIG. 8 is a cross-sectional view schematically showing an example of the substrate. FIG. 9 is a cross-sectional view schematically showing a state in which a thermosetting connecting material is provided on the terminals of the substrate. FIG. 10 is a cross-sectional view schematically showing the alignment between the terminal row of the substrate and the terminal row of the connector. FIG. 11 is a cross-sectional view schematically showing a state in which the connector is mounted on the substrate. FIG. 12 is a cross-sectional view schematically showing a state in which the substrate and the connector are heated in a reflow oven. FIG. 13 is a perspective view showing the connector structure used in the simulation. FIG. 14 is a cross-sectional view showing an example of the connector structure used in the simulation. FIG. 15 (A) is a cross-sectional view showing a first configuration example (Plug-1) of the plug, and FIG. 15 (B) is a cross-sectional view showing a second configuration example (Plug-2) of the plug. FIG. 16A is a cross-sectional view showing a third configuration example (Plug-3) of the plug, and FIG. 16B is a cross-sectional view showing a fourth configuration example (Plug-4) of the plug. FIG. 17A is a cross-sectional view showing a first L configuration example (Plug-1 Loop) of the plug, and FIG. 17B is a cross-sectional view showing a second L configuration example (Plug-2 Loop) of the plug. be. FIG. 18A is a cross-sectional view showing a third L configuration example (Plug-3 Loop) of the plug, and FIG. 18B is a cross-sectional view showing a fourth L configuration example (Plug-4 Loop) of the plug. be. FIG. 19 is a cross-sectional view showing a first configuration example (Receptacle-0) of the receptacle. FIG. 20 is a cross-sectional view showing a second configuration example (Receptacle-1) of the receptacle. FIG. 21 is a cross-sectional view showing a third configuration example (Receptacle-2) of the receptacle. FIG. 22 is a cross-sectional view showing a fourth configuration example (Receptacle-3) of the receptacle. FIG. 23 is a graph showing a transmission signal S21 when the plug of the first configuration example (Plug-1) and the receptacles of the first configuration example to the fourth configuration example (Receptacle-0 to Receptacle-3) are connected. .. FIG. 24 is a graph showing a reflection signal S11 when the plug of the first configuration example (Plug-1) and the receptacles of the first configuration example to the fourth configuration example (Receptacle-0 to Receptacle-3) are connected. .. FIG. 25 is a graph showing a transmission signal S21 when the plug of the second configuration example (Plug-2) and the receptacles of the first configuration example to the fourth configuration example (Receptacle-0 to Receptacle-3) are connected. .. FIG. 26 is a graph showing a reflection signal S11 when the plug of the second configuration example (Plug-2) and the receptacles of the first configuration example to the fourth configuration example (Receptacle-0 to Receptacle-3) are connected. .. FIG. 27 is a graph showing a transmission signal S21 when the plug of the third configuration example (Plug-3) and the receptacles of the first configuration example to the fourth configuration example (Receptacle-0 to Receptacle-3) are connected. .. FIG. 28 is a graph showing a reflection signal S11 when the plug of the third configuration example (Plug-3) and the receptacles of the first configuration example to the fourth configuration example (Receptacle-0 to Receptacle-3) are connected. .. FIG. 29 is a graph showing a transmission signal S21 when the plug of the fourth configuration example (Plug-4) and the receptacles of the first configuration example to the fourth configuration example (Receptacle-0 to Receptacle-3) are connected. .. FIG. 30 is a graph showing a reflection signal S11 when the plug of the fourth configuration example (Plug-4) and the receptacles of the first configuration example to the fourth configuration example (Receptacle-0 to Receptacle-3) are connected. .. FIG. 31 is a graph showing a transmission signal S21 when the plug of the first L configuration example (Plug-1 Loop) and the receptacles of the first configuration example to the fourth configuration example (Receptacle-0 to Receptacle-3) are connected. be. FIG. 32 is a graph showing the reflected signal S11 when the plug of the first L configuration example (Plug-1 Loop) and the receptacles of the first configuration example to the fourth configuration example (Receptacle-0 to Receptacle-3) are connected. be. FIG. 33 is a graph showing a transmission signal S21 when the plug of the second L configuration example (Plug-2 Loop) and the receptacles of the first configuration example to the fourth configuration example (Receptacle-0 to Receptacle-3) are connected. be. FIG. 34 is a graph showing the reflected signal S11 when the plug of the second L configuration example (Plug-2 Loop) and the receptacles of the first configuration example to the fourth configuration example (Receptacle-0 to Receptacle-3) are connected. be. FIG. 35 is a graph showing a transmission signal S21 when the plug of the third L configuration example (Plug-3 Loop) and the receptacles of the first configuration example to the fourth configuration example (Receptacle-0 to Receptacle-3) are connected. be. FIG. 36 is a graph showing the reflected signal S11 when the plug of the third L configuration example (Plug-3 Loop) and the receptacles of the first configuration example to the fourth configuration example (Receptacle-0 to Receptacle-3) are connected. be. FIG. 37 is a graph showing a transmission signal S21 when the plug of the 4L configuration example (Plug-4 Loop) and the receptacles of the 1st configuration example to the 4th configuration example (Receptacle-0 to Receptacle-3) are connected. be. FIG. 38 is a graph showing the reflected signal S11 when the plug of the 4L configuration example (Plug-4 Loop) and the receptacles of the 1st configuration example to the 4th configuration example (Receptacle-0 to Receptacle-3) are connected. be.

Hereinafter, embodiments of the present technology will be described in detail in the following order with reference to the drawings.
1. 1. Connection body 2. Thermosetting connection material 3. Method of manufacturing the connector 4. Connector 5. Example

<1. Connection>
The connector according to the present embodiment is a thermosetting connection material that connects a substrate having a first terminal row, a connector having a second terminal row, and a first terminal row and a second terminal row. The second terminal row is arranged on the bottom surface of the connector to form a step absorbing portion that absorbs the step on the bottom surface, and the thermosetting connecting material provides the solder particles and the flux component. It contains. As a result, the step on the bottom surface can be absorbed, so that the terminal row can be made a fine pitch and the connector can be miniaturized.

By downsizing the connection body, it is possible to reduce the weight and size of the electronic device. In addition, it is possible to reduce the size of the mounting board inside an electronic device such as a smartphone or a personal computer. In addition, the capacity of the battery can be increased. In addition, it is possible to realize functional expansion by increasing the size of various electronic components such as a larger fingerprint sensor.

Further, when the bottom surface of the connector has a step with a height in a predetermined range, it is preferable that the difference between the maximum value and the minimum value of the height of the terminal surface in the second terminal row is smaller than the height in the predetermined range. .. As a result, it is possible to absorb the step on the bottom surface of the connector and connect the first terminal row and the second terminal row.

Further, it is preferable that the difference between the maximum value and the minimum value of the height of the terminal surface in the second terminal row is smaller than the average particle size of the solder particles. As a result, the terminal row can be further reduced in pitch, and the connector can be further miniaturized.

Here, the connector is mainly a resin molded product having a fitting portion. Examples of the connector include surface mount components (SMD: Surface) such as a plug, a substrate-to-board connector for a receptacle, a board-to-flexible board (FPC: Flexible Printed Circuits), and an FPC connector for fitting an FPC by a flip lock method. Mount Device). The connecting body is one in which two materials or members are electrically connected.

FIG. 1 is a cross-sectional view schematically showing an example of a connecting body according to the present embodiment. As shown in FIG. 1, the connector includes a substrate 10 having a first terminal row 11, a connector 20 having second terminal rows 21A to 21E, and a first terminal row 11 and a second. The adhesive layer 30 is provided with a cured thermosetting connecting material for connecting the terminal row 21 of the above.

The substrate 10 has a first terminal row 11 corresponding to the second terminal rows 21A to 21E of the connector 20. The substrate 10 is not particularly limited, and examples thereof can be broadly defined as a so-called printed wiring board (PWB), and may be a rigid substrate or a flexible substrate. Examples of substrates depending on the type of substrate include glass substrates, ceramic substrates, plastic substrates, and the like.

Further, it is preferable that a short-circuit prevention process (wall, groove, etc.) by a solder resist is not formed between adjacent terminals (space portion) of the first terminal row 11. The height of the terminal surface of the first terminal row 11 may be the same as the substrate surface (the state where the terminals do not protrude and the connection surface is flat), or as shown in FIG. 1, it may protrude from the substrate surface. As a result, the first terminal row 11 and the second terminal rows 21A to 21E can be connected by solder particles, and the terminal row can be made into a fine pitch.

The connector 20 has a step absorbing portion composed of second terminal rows 21A to 21E on a surface in contact with the thermosetting connecting material. Since the connector 20 is a resin molded product, the bottom surface of the connector 20 usually has a step (waviness) having a height in the range of about 20 μm formed by the resin mold at the time of production.

The step absorbing portion aligns the heights of the terminal surfaces of the second terminal rows 21A to 21E and absorbs the step on the bottom surface of the connector 20. The difference between the maximum and minimum heights of the terminal surfaces of the second terminal rows 21A to 21E is preferably smaller than the step on the bottom surface of the connector 20 and the average particle size of the solder particles, and more preferably 10 μm or less. , More preferably 5 μm or less.

Here, the average particle size is, for example, N = 20 or more, preferably N = 50 or more, and more preferably N = in an observation image using an electron microscope such as a metallurgical microscope, an optical microscope, or an SEM (Scanning Electron Microscope). It is the average value of the major axis diameters of the particles measured at 200 or more, and when the particles are spherical, it is the average value of the diameters of the particles. In addition, the measured values and image-type grain size distribution of the observed images measured using known image analysis software ("WinROOF": Mitani Shoji Co., Ltd., "A image-kun (registered trademark)": Asahi Kasei Engineering Co., Ltd., etc.) It may be a measured value (N = 1000 or more) measured using a measuring device (for example, FPIA-3000 (Malburn)). The average particle size obtained from the observed image or the image-type particle size distribution measuring device can be the average value of the maximum lengths of the particles. When producing a thermocurable connection material, the particle size (D50) and the arithmetic mean diameter (volume basis) at which the cumulative frequency in the particle size distribution simply obtained by the laser diffraction / scattering method is 50%. The manufacturer value such as (preferably) can be used.

As shown in FIG. 1, the step absorbing portion may have terminals formed inside the resin mold as in the second terminals 21A and 21E, and may be formed on the resin mold surface as in the second terminals 21B and 21D. The terminal may be formed, or the terminal may be formed away from the resin mold surface as in the second terminal 21C. The step absorbing portion can be formed, for example, by bending a lead terminal extending toward the outside of the connector to the bottom surface of the connector and aligning the heights of the terminal surfaces. Further, the step absorbing portion can be formed, for example, by forming terminals so as to be located on the bottom surface in advance and molding the terminals with resin. Further, the terminal surface may be polished to make the height of the terminal surface uniform, if necessary.

As will be described later, the adhesive layer 30 is a film formed by curing a thermosetting connecting material containing solder particles 31 and a flux component. In the adhesive layer 30, the first terminal row 11 of the substrate 10 and the second terminal row 21 of the connector 20 are solder-bonded 32, and the thermosetting binder of the thermosetting connection material is sandwiched between the substrate 10 and the connector. Adhere by. On one terminal surface, there are a plurality of solder-bonded portions 32 and bonding portions by a thermosetting binder.

In the connector according to the present embodiment, the upper limit of the minimum value of the distance between adjacent terminals (distance between spaces) in the first terminal row 11 and the second terminal row 21 is 800 μm or less, preferably 300 μm or less. More preferably, it is 150 μm or less. Further, the lower limit of the minimum value of the distance between the adjacent terminals in the first terminal row 11 and the second terminal row 21 is 30 μm or more, more preferably 50 μm or more, still more preferably 70 μm or more.

Further, the upper limit of the ratio of the average particle size of the solder particles 31 to the minimum value of the distance between adjacent terminals in the first terminal row 11 and the second terminal row 21 is less than 0.15, more preferably 0.1. It is as follows. Further, the terminal height (distance) between the terminal surface of the first terminal row 11 and the substrate surface and the terminal height (distance) between the terminal surface of the second terminal row 21 and the bottom surface of the connector are defined. The minimum value of the total is preferably larger than the average particle size of the solder particles 31.

Further, the surfaces of the terminals of the first terminal row 11 and the second terminal row 21 may be gold-plated. Further, it is desirable that the substrate 10 and the connector 20 have heat resistance in reflow.

According to the connector according to the present embodiment, the step absorbing portion composed of the second terminal rows 21A to 21E can absorb the step on the bottom surface of the connector 20 and can be connected by solder particles. It is possible to cope with the fine pitch of the terminal row and to reduce the size of the connector.

The connector according to this embodiment is connected by solder particles widely used in solder paste, BGA (Ball grid array), etc., and has high connection reliability, so that it is a sensor device, a discrete component, and various IC chips. , Modules, eSim (Embedded Subscriber Identity Module), SoC (System on a chip), in-vehicle devices, IoT (Internet of Things) devices, and many other applications.

2 to 4 are views showing an example of a substrate-to-board connector of a plug and a receptacle according to the prior art, FIG. 2 is a top view showing an example of the plug according to the prior art, and FIG. 3 is a top view. It is a top view which shows an example of the receptacle according to the prior art, and FIG. 4 is a cross-sectional view taken along the line AA of the plug shown in FIG. 2 and the receptacle shown in FIG.

The plug 140 according to the prior art extends from the first male type vertical fitting row 141A, the second male type vertical fitting row 141B, and the first male type vertical fitting row 141A to the bottom surface. A first lead terminal row 142A extending outward in the lateral direction and a second lead terminal row 142B extending outward from the second male vertical fitting row 142A extending outward in the lateral direction. An insulating resin 143 for fixing these is provided. Further, the plug 140 according to the prior art includes a first reinforcing portion 144A provided at one end in the longitudinal direction and a second reinforcing portion 144B provided at the other end in the longitudinal direction. Since the adhesive strength is insufficient only by soldering the first lead terminal row 142A and the second lead terminal row 142B, reinforcing metal fittings are formed on the bottom surfaces of the first reinforcing portion 144A and the second reinforcing portion 144B. There are times.

Further, in the receptacle 150 according to the prior art, from the first female type vertical fitting row 151A, the second female type vertical fitting row 151B, and the first female type vertical fitting row 151A to the bottom surface. A first lead terminal row 152A extending outward in the lateral direction and a second lead terminal row 152B extending outward from the second female vertical fitting row 152A extending to the bottom surface. And an insulating resin 153 for fixing them. Further, the receptacle 150 according to the prior art includes a first reinforcing portion 154A provided at one end in the longitudinal direction and a second reinforcing portion 154B provided at the other end in the longitudinal direction. Since the adhesive strength is insufficient only by soldering the first lead terminal row 152A and the second lead terminal row 152B, the bottom surface of the first reinforcing portion 154A and the second reinforcing portion 154B is similar to the plug 140. , Reinforcing metal fittings may be formed.

The plug 140 and the receptacle 150 according to the prior art are so-called centipede type connectors in which the lead terminal row extends outward, require a relatively large mounting area, and have a smaller reinforcing portion due to insufficient adhesion. It is hindering the conversion. Further, when the bottom surface of the connector has a step having a height within a predetermined range, the average particle diameter of the solder particles must be larger than the height within the predetermined range in order to connect with the solder particles, and the terminal row Is hindering the fine pitching of.

5 to 7 are views showing an example of a substrate-to-board connector of the plug and the receptacle according to the present embodiment, and FIG. 5 is a top view showing an example of the plug according to the present embodiment. FIG. 6 is a top view showing an example of the receptacle according to the present embodiment, and FIG. 7 is a cross-sectional view taken along the line AA of the plug shown in FIG. 5 and the receptacle shown in FIG.

The plug 40 according to the present embodiment has a first male type vertical fitting row 41A, a second male type vertical fitting row 41B, and a first male type vertical fitting row 41A on the bottom surface. A first terminal row 42A extending inward in the lateral direction and a second terminal row 42B extending inward in the lateral direction extending from the second male vertical fitting row 41B to the bottom surface. The first terminal row 42A and the second terminal row 42B are provided with an insulating resin 43 for fixing them, and project from the bottom surface to form a step absorbing portion having the same height of the terminal surfaces.

Further, the receptacle 50 according to the present embodiment is from the first female type vertical fitting row 51A, the second female type vertical fitting row 51B, and the first female type vertical fitting row 51A. A first terminal row 52A extending inward in the lateral direction extending to the bottom surface and a second terminal row 52B extending inward in the lateral direction extending inward from the second female vertical fitting row 51B to the bottom surface. The first terminal row 52A and the second terminal row 52B project from the bottom surface to form a step absorbing portion having a small variation in the height of the terminal surface. ..

The first male vertical fitting row 41A of the plug 40 and the first female vertical fitting row 51A of the receptacle 50 are formed in a metal shape so as to be vertically fitted, and the second of the plug 40 is formed. The male vertical fitting row 41B and the second female vertical fitting row 51B of the receptacle 50 are formed in a metal shape so as to be vertically fitted.

The insulating resins 43 and 53 are made of, for example, polyamide, LCP, or the like, and by, for example, resin molding, the first terminal row 42A and the second terminal row 42B of the plug 40, and the first terminal row 52A and the second terminal row 52A and the second of the receptacle 50. The terminal row 52B of the above is fixed.

That is, in the plug and receptacle according to the present embodiment, the terminal row extends from the outside to the inside of the bottom surface of the connector, whereas in the plug and receptacle according to the prior art, the terminal row extends from the bottom surface to the outside of the connector. It differs in that it extends to. Further, the plug and the receptacle according to the present embodiment do not need to have a reinforcing portion, whereas the plug and the receptacle according to the prior art always have a reinforcing portion.

According to the plug and receptacle according to the present embodiment, by arranging the terminal row on the bottom surface, the mounting area can be reduced as compared with the so-called centipede type connector of the prior art. Further, since the step on the bottom surface of the connector can be absorbed, the terminal row can be made a fine pitch, and the connector can be miniaturized. Further, since the bottom surface of the connector is bonded with a thermosetting connecting material, the connector can be further miniaturized because it does not have a reinforcing portion on which a reinforcing metal fitting is formed.

<2. Thermosetting connection material>
The thermosetting connection material according to the present embodiment contains solder particles and a flux component. Since the flux component removes the solder particles and the oxide film on the terminal surface and lowers the surface tension of the molten solder, it can be connected by non-load reflow without thermocompression bonding with a tool. Here, no load means a state in which there is no mechanical pressurization during reflow.

The thermosetting connection material may be either a film-like thermosetting connection film or a paste-like thermosetting connection paste. Further, the thermosetting connection paste may be formed into a film at the time of connection, or may be formed into a form similar to a film by mounting a component.

In the case of a thermosetting connection paste, it suffices if a predetermined amount can be uniformly applied onto the substrate. For example, application methods such as dispensing, stamping, and screen printing can be used, and the paste may be dried if necessary. .. In this case, it can be expected that capital investment can be suppressed by diverting, modifying and applying the conventionally used solder paste equipment.

In the case of a thermosetting connection film, not only can the amount of bonding material (for example, anisotropic conductive material) be made uniform depending on the film thickness, but also it can be laminated on the substrate all at once, and the tact can be shortened. It is especially preferable because it can be done. In addition, since it is easy to handle by forming it into a film in advance, it can be expected that the work efficiency will be improved.

Further, in the case of a heat-curable connection film, since it can be laminated on the substrate at once, not only the connector but also various electronic parts such as discrete parts, various IC chips, modules, eSim, and SoC should be mounted at once. It is also possible to shorten the tact time and fine pitch of various electronic components. In addition, fine pitching of various electronic components makes it possible to reduce the distance between adjacent mounting components and enable high-density mounting. Fine pitching of various electronic components leads to smaller components, for example, an increase in the number of components cut out from one wafer, and cost reduction can be achieved. Further, not only the wafer but also various electronic parts can be reduced in cost by making the parts smaller.

Further, the connection using the thermosetting connection material is not limited to the above-mentioned parts, and the SMT part has a connection terminal for conductivity, and the height of the connection terminal becomes flat or convex with respect to the bottom surface. It can be applied to all existing shapes. In addition, various electronic components fixed with a thermosetting connecting material and various electronic components fixed with a connecting material such as solder paste can be simultaneously put into reflow and connected.

The minimum melt viscosity of the thermosetting connecting material may be less than 100 Pa · s, preferably 50 Pa · s or less, more preferably 30 Pa · s or less, still more preferably 10 Pa · s or less. If the minimum melt viscosity is too high, the resin will not melt under no load during reflow, which may hinder the sandwiching between the solder particles and the terminals. The temperature at which the minimum melt viscosity of the thermosetting connection material is reached is preferably −10 ° C. to −60 ° C., which is the melting point of the solder particles, more preferably −10 ° C. to −50 ° C., which is the melting point of the solder particles, and more preferably solder. The melting point of the particles is −10 ° C. to −40 ° C. As a result, the minimum melt viscosity is reached before the solder melts, the resin is melted, the solder particles are melted after the resin is melted, and then the resin is cured, so that a good solder bond can be obtained. Here, the minimum melt viscosity reaching temperature of the thermosetting connecting material is, for example, using a rotary rheometer (manufactured by TA instrument), measuring pressure 5 g, temperature range 30 to 200 ° C., heating rate 10 ° C./min. It refers to the temperature at which the viscosity becomes the minimum value (minimum melt viscosity) when measured under the conditions of a measurement frequency of 10 Hz, a measurement plate diameter of 8 mm, and a load fluctuation of 5 g with respect to the measurement plate.

Further, the thermosetting connection material preferably has a heat generation 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. As a result, after the thermosetting binder is melted, the solder is melted in a state where the solder particles are sandwiched between the terminals, so that a fine pitch terminal row can be joined. Here, the exothermic peak temperature can be measured under the conditions of a temperature range of 30 to 250 ° C. and a heating rate of 10 ° C./min by measuring 5 mg or more of the sample with an aluminum pan by differential scanning calorimetry (DSC).

When the thermosetting connection material is in the form of a film, the lower limit of the ratio of the average particle size of the solder particles to the thickness of the thermosetting connection material is preferably 0.5 or more, more preferably 0.6 or more. As a result, the solder particles can be easily sandwiched between the terminals, and can correspond to a fine pitch terminal row. Here, the film thickness is measured using a known micrometer or digital thickness gauge (for example, Mitutoyo Co., Ltd .: MDE-25M, minimum display amount 0.0001 mm) capable of measuring 1 μm or less, preferably 0.1 μm or less. be able to. The film thickness may be obtained by measuring 10 or more points and averaging them. However, if the film thickness is thinner than the particle size, a contact-type thickness measuring instrument is not suitable, so it is preferable to use a laser displacement meter (for example, KEYENCE Co., Ltd., spectroscopic interference displacement type SI-T series, etc.). .. The film thickness is the thickness of the resin layer only, and does not include the particle size. Further, the average particle size can be confirmed by arbitrarily extracting 5 or more areas ^{of 1 mm 2} or more in a film plan view using a known metal microscope or optical microscope.

[Solder particles]
The solder particles may or may not be those specified in JIS Z 3282-1999, for example, Sn-Pb system, Pb-Sn-Sb system, Sn-Sb system, Sn-Pb-. From Bi system, Bi-Sn system, Sn-Bi-Cu system, Sn-Cu system, Sn-Pb-Cu system, Sn-In system, Sn-Ag system, Sn-Pb-Ag system, Pb-Ag system, etc. , Can be appropriately selected according to the terminal material, connection conditions, and the like.

The lower limit of the melting point of the solder particles is preferably 110 ° C. or higher, more preferably 120 ° C. or higher, still more preferably 130 ° C. or higher. The upper limit of the melting point of the solder particles may be 200 ° C. or lower, preferably 180 ° C. or lower, more preferably 160 ° C. or lower, and further preferably 150 ° C. or lower. Further, the solder particles may have a flux compound directly bonded to the surface for the purpose of activating the surface. By activating the surface, metal bonding with terminals can be promoted.

The average particle size of the solder particles is preferably 0.2 times or less the minimum value of the inter-terminal distance (inter-space distance) in the first terminal row of the substrate and the second terminal row of the connector. When the average particle size of the solder particles is larger than 0.2 times the minimum value of the distance between the terminals in the first terminal row of the substrate and the second terminal row of the connector, the possibility of a short circuit increases.

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. If the average particle size of the solder particles is smaller than 0.5 μm, a good solder bonding state with the terminal cannot be obtained, and the reliability tends to deteriorate. The upper limit of the average particle size of the solder particles may be 50 μm or less, 30 μm or less, preferably 20 μm or less, and more preferably 10 μm or less.

The maximum diameter of the solder particles can be 200% or less of the average particle size, preferably 150% or less of the average particle size, and more preferably 120% or less of the average particle size. When the maximum diameter of the solder particles is within the above range, the solder particles can be sandwiched between the terminals, and the terminal rows can be joined by melting the solder particles.

Further, the solder particles may be agglomerates in which a plurality of the solder particles are agglomerated. When a plurality of solder particles are agglomerated, the size of the agglomerates may be equal to the average particle size of the above-mentioned solder particles. The size of the aggregate can be determined by observing it with an electron microscope or an optical microscope.

The lower limit of the mass ratio range of the blended amount of solder particles is preferably 10 wt% or more, more preferably 20 wt% or more, still more preferably 30 wt% or more, and the upper limit of the mass ratio range of the blended amount of solder particles is 70 wt% or more. Below, it is more preferably 60 wt% or less, still more preferably 50 wt% or less.

If the blending amount of the solder particles is too small, excellent conductivity cannot be obtained, and if the blending amount is too large, the insulation between the terminals is likely to be impaired, and it becomes difficult to obtain excellent conduction reliability. When the solder particles are present in the thermosetting binder, the volume ratio may be used, and when the thermosetting connection material is produced (before the solder particles are present in the binder), the mass ratio is used. You may use it. The mass ratio can be converted into a volume ratio from the specific gravity of the compound, the compounding ratio, and the like.

The solder particles are preferably dispersed in a thermosetting binder, and the solder particles may be arranged randomly or according to a certain rule. As a mode of regular arrangement, a lattice arrangement such as a square lattice, a hexagonal lattice, an orthorhombic lattice, and a rectangular lattice can be mentioned. Further, the solder particles may be arranged as agglomerates in which a plurality of the solder particles are agglomerated. In this case, the arrangement of the agglomerates in the plan view of the thermosetting connecting material may be a regular arrangement or a random arrangement as in the arrangement of the solder particles described above.

[Flux component]
As the flux component, for example, it is preferable to use a carboxylic acid such as levulinic acid, maleic acid, oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, and sebacic acid. As a result, a good solder connection can be obtained, and when an epoxy resin is blended, it can function as a curing agent for the epoxy resin.

Further, as the flux compound, a blocked carboxylic acid in which the carboxyl group is blocked with an alkyl vinyl ether may be used. Thereby, it is possible to control the temperature at which the flux effect and the curing agent function are exhibited. Further, since the solubility in the resin is improved, it is possible to improve the mixing / coating unevenness at the time of forming a film.

[Thermosetting binder]
Examples of the thermocurable binder (insulating binder) include a thermal radical polymerization type resin composition containing a (meth) acrylate compound and a thermal radical polymerization initiator, and a thermal cationic polymerization type resin containing an epoxy compound and a thermal cationic polymerization initiator. Examples thereof include a composition, a thermal anionic polymerization type resin composition containing an epoxy compound and a thermal anionic polymerization initiator. Moreover, you may use a known pressure-sensitive adhesive composition. The (meth) acrylic monomer means to include both an acrylic monomer and a methacrylic monomer.

Hereinafter, 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 will be described as an example.

The solid epoxy resin is not particularly limited as long as it is an epoxy resin that is solid at room temperature and has one or more epoxy groups in the molecule, and is, for example, a bisphenol A type epoxy resin, a biphenyl type epoxy resin, or the like. There may be. Thereby, the film shape can be maintained. Here, the normal temperature is in the range of 20 ° C. ± 15 ° C. (5 ° C. to 35 ° C.) defined by JIS Z 8703.

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 type epoxy resin, a bisphenol F type epoxy resin, or a urethane-modified epoxy resin. No.

The blending amount of the liquid epoxy resin is preferably 160 parts by mass or less, more preferably 100 parts by mass or less, and further preferably 70 parts by mass or less with respect to 100 parts by mass of the solid epoxy resin. When the amount of the liquid epoxy resin blended is large, it becomes difficult to maintain the film shape.

The epoxy resin curing agent is not particularly limited as long as it is a thermosetting agent that starts curing by 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 so as to obtain resistance to the solvent used for film formation.

[Other additives]
In addition to the above-mentioned insulating binder and solder particles, the thermosetting connection material should contain various additives conventionally used in heat-curable adhesives as long as the effects of the present invention are not impaired. Can be done. The particle size of the additive is preferably smaller than the average particle size of the solder particles, but is not particularly limited as long as it does not hinder the bonding between terminals. For example, a spacer may be blended for balance adjustment. As the spacer, for example, monodisperse silica (for example, "High Presica" manufactured by Ube Exsymo Co., Ltd.) may be appropriately blended according to the particle size of the solder.

In the above-mentioned thermosetting connection material, for example, an insulating binder and solder particles are mixed in a solvent, the mixture is applied to a peeling film by a bar coater to a predetermined thickness, and then dried. It can be obtained by volatilizing the solvent. Further, the mixture may be applied on the peeling film by a bar coater and then pressed to a predetermined thickness. Further, in order to increase the dispersibility of the solder particles, it is preferable to apply a high share in a state containing a solvent. For example, a known batch type planetary stirrer can be used. The amount of residual solvent in the thermosetting connecting material is preferably 2% or less, more preferably 1% or less.

<3. Manufacturing method of connector>
In the method for manufacturing a connector according to the present embodiment, a second terminal row is arranged on the bottom surface of a substrate having a first terminal row via a thermosetting connecting material containing solder particles and a flux component. A connector having a step absorbing portion for absorbing the step on the bottom surface is placed, and the thermosetting connection material is thermoset at a temperature equal to or higher than the melting point of the solder particles without pressing the connector to heat the first terminal. Connect the row to the second terminal row. As a result, the step on the bottom surface can be absorbed, so that the terminals can be made into a fine pitch and the connector can be miniaturized.

Hereinafter, with reference to FIGS. 8 to 12, a step of providing a thermosetting connection material on the first terminal row of the substrate (A) and a step of placing the connector on the thermosetting connection material (B). A step (C) of joining the first terminal row of the substrate and the second terminal row of the connector by using a reflow furnace set to a temperature equal to or higher than the melting point of the solder particles will be described. The same components as those shown in FIG. 1 are designated by the same reference numerals, and the description thereof will be omitted here.

[Step (A)]
FIG. 8 is a cross-sectional view schematically showing an example of a substrate, and FIG. 9 is a cross-sectional view schematically showing a state in which a thermosetting connecting material is provided on a terminal of the substrate. As shown in FIGS. 8 and 9, in the step (A), the thermosetting connection material 33 containing the solder particles 31 is provided on the first terminal row 11 of the substrate 10.

The step (A) may be a step of forming the thermosetting connection paste into a film on the substrate, and as used in the conventional conductive film or anisotropic conductive film, the thermosetting connection film is formed. It may be a temporary sticking step of sticking on the substrate at a low temperature, or a laminating step of laminating a thermosetting connection film on the substrate.

When the step (A) is a temporary pasting step, a thermosetting connection film can be provided on the substrate under known usage conditions. In this case, only minimal changes such as installation and change of tools from the conventional device are required, which is economically advantageous.

When the step (A) is a laminating step, for example, a thermosetting connection film is laminated on the substrate using a pressure type laminator. The laminating step may be a vacuum pressurization type. In the case of temporary pasting using a conventional conductive film or anisotropic conductive film heating / pressing tool, the width of the film is restricted by the tool width, but in the laminating process, the heating / pressing tool is not used. It can be expected that a relatively wide width can be mounted all at once.

In the step (A), 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, still more preferably 0. 9 or more. As a result, the solder particles can be easily sandwiched between the terminals, and can correspond to a fine pitch terminal row.

[Step (B)]
FIG. 10 is a cross-sectional view schematically showing the alignment between the terminal row of the substrate and the terminal row of the connector. As shown in FIG. 10, in the step (B), for example, the tool 60 is used to align the terminal row 11 of the substrate 10 with the terminal row 31 of the connector 30, and the connector 30 is placed on the thermosetting connection material 20. Is placed. The tool 60 preferably includes a suction mechanism that sucks the connector 20. Since self-alignment by solder cannot be expected in this technique, it is desirable to accurately align the connector 20 and fix it with the thermosetting connection material 33 in the step (B).

[Step (C)]
FIG. 11 is a cross-sectional view schematically showing a state in which the connector is placed on the substrate, and FIG. 12 is a cross-sectional view schematically showing a state in which the substrate and the connector are heated in a reflow oven. As shown in FIGS. 11 and 12, in step (C), a reflow furnace set above the melting point of the solder particles 31 is used, and the first terminal row 11 of the substrate 10 and the second terminal 21 of the connector 20 are used. To join.

Since the reflow furnace can be heat-bonded without a load without mechanical pressurization, damage to the substrate 10 and the connector 20 can be suppressed. Further, since there is no load, the amount of movement of the solder particles is small, and it is possible to correspond to a fine pitch terminal row.

As the reflow furnace, atmospheric pressure reflow is preferable from the viewpoint of simplicity, but atmospheric pressure reflow, vacuum reflow, atmospheric pressure oven, autoclave (pressurized oven) and the like may be used.

The lower limit of the peak temperature (maximum temperature reached) in the reflow oven may be at least the temperature at which the solder particles melt and at least the temperature at which the thermosetting binder starts to cure, preferably 150 ° C. or higher, more preferably 180. ° C. or higher, more preferably 200 ° C. or higher. The upper limit of the peak temperature in the reflow furnace is 300 ° C. or lower, more preferably 290 ° C. or lower, and further preferably 280 ° C. or lower. As a result, the first terminal row 11 of the substrate 10 and the second terminal row 21 of the connector 20 can be joined 32.

According to the method for manufacturing a connecting body according to the present embodiment, since the step on the bottom surface can be absorbed, the terminals can be made fine pitch and the connecting body can be miniaturized. When the thermosetting connection material is a thermosetting binder, the temperature rise / maintenance / temperature decrease in the reflow process is combined with the thermosetting behavior of the thermosetting connection material to melt the resin in the reflow process and between the terminals. It is possible to optimize the sandwiching of solder particles, melting of solder, and curing of resin. The thermosetting behavior of the thermosetting connection material can be known by DSC measurement or viscosity measurement with a rheometer.

<4. Connector>
Next, the terminal structure of the connector to which this technique is applied will be described. Since the conventional connector is surface-mounted by soldering, the terminal row has a structure extending from the inside to the outside of the connector. Therefore, an open end called a stub may be created, which may adversely affect the frequency characteristics. For example, the open end portion has a frequency characteristic that resonance occurs at a frequency whose length becomes 1/4 wavelength and the signal level at that frequency becomes 0.

In the connector to which this technology is applied, since the terminal row does not need to extend from the bottom surface to the outside, the degree of freedom of the terminal structure is increased, and the terminal structure having excellent high frequency characteristics can be selected. Hereinafter, the combination of the terminal structure of the plug and the receptacle was simulated and evaluated by S-parameters (Scattering parameters).

FIG. 13 is a perspective view showing the connector structure used in the simulation, and FIG. 14 is a cross-sectional view showing an example of the connector structure used in the simulation. The wiring board model was an FPC (Flexible printed circuits) with a coverlay having a wiring pitch of 0.35 mm and a wiring thickness of 18 μm, and the wiring width was optimized. The wiring width at which the impedance is 100Ω is 0.25 mm.

As shown in FIGS. 13 and 14, in a connector connection using a coplanar differential line, a simulation was performed in which a plug was mounted on the first FPC 71 and a receptacle was mounted on the second FPC 72. The plug is selected from the shapes shown in FIGS. 15 to 18, and the receptacle is selected from the shapes shown in FIGS. 19 to 22. Regarding the influence of the combination of the plug and the receptacle on the transmission characteristics, the transmission signal S21 and the reflected signal It was evaluated according to S11. The transmission signal S21 is a signal that passes through the terminal B of the second FPC 72 when the signal is input from the terminal A of the first FPC 71, and the decibel display of the absolute value is the insertion loss from the terminal A to the terminal B (the insertion loss from the terminal A to the terminal B. Insertion loss) is shown. The reflected signal S11 is a signal that is reflected to the terminal A when a signal is input from the terminal A of the first FPC 71, and the decibel display of the absolute value indicates the reflection loss (return loss) of the terminal A.

FIG. 15 (A) is a cross-sectional view showing a first configuration example (Plug-1) of the plug, and FIG. 15 (B) is a cross-sectional view showing a second configuration example (Plug-2) of the plug. In the first configuration example, a connecting portion 81a extending linearly in the horizontal direction (X-axis direction) from the first end portion and being connected to the wiring, and a connecting portion 81a bent in the vertical direction (Y-axis direction) to form a straight line. It is provided with a male vertical fitting portion 82b which extends inward of the connecting portion 81a due to a semicircular shape and serves as a second end portion. The second configuration example is symmetrical with the first configuration example, and extends linearly in the horizontal direction (X-axis direction) from the first end portion and is connected to the wiring, and the connection portion 82a and the connection portion 82a in the vertical direction. It is provided with a male vertical fitting portion 82b that bends in the (Y-axis direction), extends linearly, extends inward of the connecting portion 82a due to a semicircular shape, and serves as a second end portion. Then, the first configuration example is implemented with the orientation of the end portion of the wiring of the first FPC 71 aligned with the orientation of the first end portion, and the second configuration example is the orientation of the end portion of the wiring of the first FPC 71. And the opposite direction of the first end are aligned.

FIG. 16A is a cross-sectional view showing a third configuration example (Plug-3) of the plug, and FIG. 16B is a cross-sectional view showing a fourth configuration example (Plug-4) of the plug. In the third configuration example, the connecting portion 83a extending linearly from the first end in the horizontal direction (X-axis direction) and being connected to the wiring, and the connecting portion 83a are bent in the vertical direction (Y-axis direction) to form a straight line. It is provided with a male vertical fitting portion 83b which extends to the outside of the connecting portion 83a due to a semicircular shape and serves as a second end portion. The fourth configuration example is symmetrical with the third configuration example, and extends linearly in the horizontal direction (X-axis direction) from the first end portion and is connected to the wiring, and the connection portion 84a and the connection portion 84a in the vertical direction. It is provided with a male vertical fitting portion 84b that bends in the (Y-axis direction), extends linearly, extends outside the connecting portion 84a due to a semicircular shape, and serves as a second end portion. That is, in the third configuration example and the fourth configuration example, the semicircular shape is extended to the outside of the connecting portion 83a in the first configuration example and the second configuration example, respectively. Then, the third configuration example is mounted so that the direction of the end portion of the wiring of the first FPC 71 and the opposite direction of the first end portion are aligned, and the fourth configuration example is the end portion of the wiring of the first FPC 71. It is mounted with the orientation aligned with the orientation of the first end.

FIG. 17A is a cross-sectional view showing a first L configuration example (Plug-1 Loop) of the plug, and FIG. 17B is a cross-sectional view showing a second L configuration example (Plug-2 Loop) of the plug. be. In the first L configuration example, a connecting portion 85a extending linearly in the horizontal direction (X-axis direction) from the first end portion and being connected to the wiring, and a connecting portion 85a bent in the vertical direction (Y-axis direction) to form a linear shape. It is provided with a male vertical fitting portion 85b that extends inwardly of the connecting portion 85a due to the semicircular shape and is connected to the connecting portion 85a by the semicircular shape. The second L configuration example is symmetrical with the first L configuration example, and extends linearly in the horizontal direction (X-axis direction) from the first end portion and is connected to the wiring, and the connection portion 86a and the connection portion 86a in the vertical direction. It is provided with a male vertical fitting portion 86b that bends in the (Y-axis direction), extends linearly, extends inward of the connecting portion 86a due to the semicircular shape, and is connected to the connecting portion 86a by the semicircular shape. That is, in the first configuration example and the second configuration example, in the first configuration example and the second configuration example, the second end portion is connected to the connection portion by a semicircular shape, respectively. Then, the first L configuration example is implemented with the orientation of the end portion of the wiring of the first FPC 71 aligned with the orientation of the first end portion, and the second L configuration example is the orientation of the end portion of the wiring of the first FPC 71. And the opposite direction of the first end are aligned.

FIG. 18A is a cross-sectional view showing a third L configuration example (Plug-3 Loop) of the plug, and FIG. 18B is a cross-sectional view showing a fourth L configuration example (Plug-4 Loop) of the plug. be. The third L configuration example extends linearly from the first end in the horizontal direction (X-axis direction) and bends in the vertical direction (Y-axis direction) from the connecting portion 87a connected to the wiring and linearly. It is provided with a male vertical fitting portion 86b that extends to the outside of the connecting portion 86a due to the semicircular shape and is connected to the connecting portion 86a by the semicircular shape. The fourth L configuration example is bilaterally symmetrical with the third L configuration example, and extends linearly from the first end in the horizontal direction (X-axis direction) and is connected to the wiring. It is provided with a male vertical fitting portion 88b that bends in the (Y-axis direction), extends linearly, extends outside the connecting portion 88a by a semicircular shape, and connects to the connecting portion 88a by a semicircular shape. That is, in the third configuration example and the fourth configuration example, in the third configuration example and the fourth configuration example, the second end portion is connected to the connection portion by a semicircular shape, respectively. Then, the third L configuration example is mounted so that the direction of the end portion of the wiring of the first FPC 71 and the opposite direction of the first end portion are aligned, and the fourth L configuration example is the end portion of the wiring of the first FPC 71. It is mounted with the orientation aligned with the orientation of the first end.

FIG. 19 is a cross-sectional view showing a first configuration example (Receptacle-0) of the receptacle. In the first configuration example, a connecting portion 91a extending linearly in the horizontal direction (X-axis direction) from the first end portion and being connected to the wiring, and a connecting portion 91a bent in the vertical direction (Y-axis direction) to form a straight line. The vertical portion 91b and the vertical portion 91b extend linearly from the vertical portion 91b to the outside of the connecting portion 91a in the vertical direction (Y-axis direction), bend outward in the horizontal direction (X-axis direction), and extend linearly. A female vertical fitting portion 91c that bends inward again in the vertical direction (Y-axis direction), further bends inward, and becomes a second end portion due to a semicircular shape is provided. Then, the first configuration example is mounted so that the direction of the end portion of the wiring of the second FPC 72 and the opposite direction of the first end portion are aligned.

FIG. 20 is a cross-sectional view showing a second configuration example (Receptacle-1) of the receptacle. In the second configuration example, the connecting portion 92a extending linearly from the first end in the horizontal direction (X-axis direction) and being connected to the wiring, and the connecting portion 92a are bent in the vertical direction (Y-axis direction) to form a straight line. The vertical portion 92b and the vertical portion 92b extend linearly in the vertical direction (Y-axis direction) inside the connecting portion 92a due to a semicircular shape, bend outward in the horizontal direction (X-axis direction), and extend linearly. A female vertical fitting portion 92c that bends inward again in the vertical direction (Y-axis direction), further bends inward, and becomes a second end portion due to a semicircular shape is provided. That is, in the second configuration example, in the first configuration example, the connecting portion is bent toward the female vertical fitting portion. Then, the second configuration example is implemented so that the orientation of the end portion of the wiring of the second FPC 72 and the orientation of the first end portion are aligned.

FIG. 21 is a cross-sectional view showing a third configuration example (Receptacle-2) of the receptacle. In the third configuration example, a vertical portion 93a extending linearly in the vertical direction (Y-axis direction) from the first end portion and a vertical portion 93a bent in the horizontal direction (X-axis direction) from the vertical portion 93a and extending linearly to be connected to a wiring. The connecting portion 93b to be formed and the connecting portion 93b are bent inward in the vertical direction (Y-axis direction) and further bent inward to become the second end portion due to the semicircular shape, and the vertical portion 93a and the connecting portion 93b are constituent elements. It is provided with a female vertical fitting portion 93c. Then, the third configuration example is mounted so that the vertical portion 93a is inside with respect to the direction of the end portion of the wiring of the second FPC 72.

FIG. 22 is a cross-sectional view showing a fourth configuration example (Receptacle-3) of the receptacle. The fourth configuration example is symmetrical with the third configuration example, and has a vertical portion 94a extending linearly from the first end portion in the vertical direction (Y-axis direction) and a vertical portion 94a extending linearly from the vertical portion 94a in the horizontal direction (X-axis direction). A connection part 94b that bends, extends linearly, and is connected to the wiring, and bends inward in the vertical direction (Y-axis direction) from the connection part 94b, and then bends inward, becoming the second end due to the semicircular shape, and is vertical. A female vertical fitting portion 94c having a portion 94a and a connecting portion 94b as constituent elements is provided. Then, the fourth configuration example is mounted so that the vertical portion 94a is on the outside with respect to the direction of the end portion of the wiring of the second FPC 72.

[High frequency characteristics of the first configuration example to the fourth configuration example (Plug-1 to Plug-4)]
FIG. 23 is a graph showing a transmission signal S21 when the plug of the first configuration example (Plug-1) and the receptacles of the first configuration example to the fourth configuration example (Receptacle-0 to Receptacle-3) are connected. 24 is a graph showing the reflected signal S11 when the plug of the first configuration example (Plug-1) and the receptacles of the first configuration example to the fourth configuration example (Receptacle-0 to Receptacle-3) are connected. be.

FIG. 25 is a graph showing a transmission signal S21 when the plug of the second configuration example (Plug-2) and the receptacles of the first configuration example to the fourth configuration example (Receptacle-0 to Receptacle-3) are connected. 26 is a graph showing the reflected signal S11 when the plug of the second configuration example (Plug-2) and the receptacles of the first configuration example to the fourth configuration example (Receptacle-0 to Receptacle-3) are connected. be.

FIG. 27 is a graph showing a transmission signal S21 when the plug of the third configuration example (Plug-3) and the receptacles of the first configuration example to the fourth configuration example (Receptacle-0 to Receptacle-3) are connected. 28 is a graph showing the reflected signal S11 when the plug of the third configuration example (Plug-3) and the receptacles of the first configuration example to the fourth configuration example (Receptacle-0 to Receptacle-3) are connected. be.

FIG. 29 is a graph showing a transmission signal S21 when the plug of the fourth configuration example (Plug-4) and the receptacles of the first configuration example to the fourth configuration example (Receptacle-0 to Receptacle-3) are connected. FIG. 30 is a graph showing a reflection signal S11 when the plug of the fourth configuration example (Plug-4) and the receptacles of the first configuration example to the fourth configuration example (Receptacle-0 to Receptacle-3) are connected. be.

From the graphs shown in FIGS. 23 to 30, the combination of the terminal structure of the plug and the receptacle is, for example, the first configuration example (Receptacle-0) or the second configuration example with respect to the plug of the first configuration example (Plug-1). The receptacle of (Receptacle-1) is preferable, and the receptacle of the fourth configuration example (Receptacle-3) is preferable to the plug of the second configuration example (Plug-2), and the plug of the third configuration example (Plug-3) is used. On the other hand, the receptacle of the first configuration example (Receptacle-0) or the receptacle of the second configuration example (Receptacle-1) is preferable, and the plug of the fourth configuration example (Plug-4) is compared with the plug of the fourth configuration example (Receptacle-3). Receptacles have been found to be preferred.

[High frequency characteristics of 1st L configuration example to 4th L configuration example (Plug-1 Loop to Plug-4 Loop)]
FIG. 31 is a graph showing a transmission signal S21 when the plug of the first L configuration example (Plug-1 Loop) and the receptacles of the first configuration example to the fourth configuration example (Receptacle-0 to Receptacle-3) are connected. FIG. 32 shows a reflection signal S11 when the plug of the first L configuration example (Plug-1 Loop) and the receptacles of the first configuration example to the fourth configuration example (Receptacle-0 to Receptacle-3) are connected. It is a graph.

FIG. 33 is a graph showing a transmission signal S21 when the plug of the second L configuration example (Plug-2 Loop) and the receptacles of the first configuration example to the fourth configuration example (Receptacle-0 to Receptacle-3) are connected. FIG. 34 shows a reflection signal S11 when the plug of the second L configuration example (Plug-2 Loop) and the receptacles of the first configuration example to the fourth configuration example (Receptacle-0 to Receptacle-3) are connected. It is a graph.

FIG. 35 is a graph showing a transmission signal S21 when the plug of the third L configuration example (Plug-3 Loop) and the receptacles of the first configuration example to the fourth configuration example (Receptacle-0 to Receptacle-3) are connected. FIG. 36 shows a reflection signal S11 when the plug of the third L configuration example (Plug-3 Loop) and the receptacles of the first configuration example to the fourth configuration example (Receptacle-0 to Receptacle-3) are connected. It is a graph.

FIG. 37 is a graph showing a transmission signal S21 when the plug of the 4L configuration example (Plug-4 Loop) and the receptacles of the 1st configuration example to the 4th configuration example (Receptacle-0 to Receptacle-3) are connected. FIG. 38 shows a reflection signal S11 when the plug of the 4L configuration example (Plug-4 Loop) and the receptacles of the 1st configuration example to the 4th configuration example (Receptacle-0 to Receptacle-3) are connected. It is a graph.

From the graphs shown in FIGS. 31 to 38, the combination of the terminal structure of the plug and the receptacle is, for example, the third configuration example (Receptacle-2) or the fourth configuration with respect to the plug of the first L configuration example (Plug-1 Loop). The receptacle of the example (Receptacle-3) is preferable, and the receptacle of the third configuration example (Receptacle-2) or the fourth configuration example (Receptacle-3) is preferable to the plug of the second L configuration example (Plug-2 Loop). The receptacle of the third configuration example (Receptacle-2) or the fourth configuration example (Receptacle-3) is preferable to the plug of the third L configuration example (Plug-3 Loop), and the receptacle of the fourth L configuration example (Plug-4 Loop) is preferable. It was found that the receptacle of the third configuration example (Receptacle-2) or the fourth configuration example (Receptacle-3) is preferable for the plug.

[Simulation evaluation]
In the conventional solder mounting, the terminal has a structure extending outward from the bottom surface of the connector, and the connection between the plug of the fourth configuration example (Plug-4) and the receptacle of the first configuration example (Receptacle-0), and the connection thereof. There is only a combination of inversions. Further, in the solder mounting connector, stubs occur because one side of both terminals always has the opposite direction of electricity flow. Further, in the conventional solder mounting, the thickness of the solder in the Z direction is as high as 0.1 to 1 mm, which is not suitable for high frequency characteristics.

On the other hand, in the connection using the thermosetting connection material according to the present technology, it is not necessary for the terminals to extend from the bottom surface of the connector to the outside, and the connector allows the orientation of the terminals to be selected for both terminals. It is possible to select the traveling direction of the current flow, reduce the influence of stubs, and improve the high frequency characteristics. Further, by making the plug a loop structure, the influence of the stub can be further reduced. Further, the thickness of the thermosetting connecting material is 1 to 30 μm, which is about 1/10 of the thickness of the solder, and the high frequency characteristics can be improved.

According to this technology, it is possible to use a region corresponding to high frequencies that could not be used with the conventional B2B connector, and to expand the region. Therefore, a connector having excellent high frequency characteristics can be used for communication electronic devices such as smartphones. Further, by using the high frequency connector, it is possible to replace the board when the board is broken at a lower cost than the coaxial connector.

<5. Example>
In this example, an anisotropic conductive film containing solder particles was produced as a thermosetting connection material. Then, using the anisotropic conductive film, the substrate-to-board connectors of the plug and the receptacle were mounted on the substrate, respectively, and the initial continuity evaluation of the mounted body and the continuity evaluation after the insertion / removal test were performed. The present embodiment is not limited to these.

[Initial continuity evaluation]
For the plug mounting body sample and the receptacle mounting body sample, the resistance value when a current of 1 mA was passed between the terminal of the connector and the terminal of the corresponding substrate was measured, and the median value was calculated. A mounting body having a median resistance value of 1.0Ω or less was evaluated as "OK", and other mounting bodies were evaluated as "NG".

[Continuity evaluation after insertion / removal test]
The insertion / removal test was performed 10 times using the plug mounting body sample and the receptacle mounting body sample. The plug mount sample and the receptacle mount sample after the insertion / removal test were evaluated in the same manner as the initial continuity evaluation.

[Preparation of ACF-A]
As shown in Table 1, 80 parts by mass of solid epoxy resin (bisphenol F type epoxy resin, Mitsubishi Chemical Co., Ltd., JER4007P, softening point 108 ° C.), liquid epoxy resin (dicyclopentadiene skeleton epoxy resin, ADEKA Co., Ltd.) , EP4088L) by 20 parts by mass, epoxy resin curing agent (imidazole-based curing agent, Shikoku Kasei Kogyo Co., Ltd., Curesol 2P4MHZ-PW) by 5 parts by mass, flux compound (glutaric acid (1,3-propanedicarboxylic acid), Tokyo Kasei Co., Ltd. is blended with 3 parts by mass and 50 parts by mass of solder particles (MCP-137, 5N Plus inc, Sn-58Bi alloy, solid phase line temperature 138 ° C.) having an average particle diameter of 30 μm, and is anisotropic. A conductive film (ACF-A) was produced. The minimum melt viscosity of the anisotropic conductive film was 6.1 Pa · s, and the temperature at which the minimum melt viscosity was reached was 114 ° C. The exothermic peak temperature of the anisotropic conductive film was 163 ° C.

A flux compound MEK (methyl ethyl ketone) dissolved product and an epoxy resin curing agent were mixed with a solid epoxy resin and a liquid epoxy resin dissolved in PMA (propylene glycol monomethyl ether acetate). After the solder particles are dispersed in this mixed solution, it is coated on a PET (polyethylene terephthalate) film so that the thickness after solvent drying with a gap coater is +5 μm of the average particle size of the solder particles, and is anisotropic. A conductive film (ACF-A) was produced. Drying was carried out under the condition of 70 ° C.-5 min.

[Preparation of ACF-B]
As shown in Table 1, it is anisotropic like ACF-A except that solder particles having an average particle diameter of 20 μm (MCP-137, 5N Plus inc, Sn-58Bi alloy, solid phase temperature of 138 ° C.) are used. A conductive film (ACF-B) was produced. The minimum melt viscosity of the anisotropic conductive film was 6.1 Pa · s, and the temperature at which the minimum melt viscosity was reached was 114 ° C. The exothermic peak temperature of the anisotropic conductive film was 163 ° C.

[Preparation of ACF-C]
As shown in Table 1, it is anisotropic like ACF-A except that solder particles having an average particle diameter of 10 μm (MCP-137, 5N Plus inc, Sn-58Bi alloy, solid phase temperature of 138 ° C.) are used. A conductive film (ACF-C) was produced. The minimum melt viscosity of the anisotropic conductive film was 6.1 Pa · s, and the temperature at which the minimum melt viscosity was reached was 114 ° C. The exothermic peak temperature of the anisotropic conductive film was 163 ° C.

[Preparation of ACF-D]
As shown in Table 1, 15 parts by mass of liquid epoxy resin (manufactured by Mitsubishi Chemical Corporation: EP828), 20 parts by mass of phenoxy resin (manufactured by Nippon Steel Chemical Co., Ltd .: YP50), butadiene-acrylonitrile rubber (product name: XER) -91, manufactured by JSR Corporation) 18 parts by mass, hydroxyl group-containing acrylic rubber (product name: SG-80H, manufactured by Nagase ChemteX Corporation) 4 parts by mass, microcapsule type amine-based curing agent (manufactured by Asahi Kasei E-Materials Co., Ltd .: Novacure HX3941HP) ) To 40 parts by mass and 50 parts by mass of solder particles (MCP-137, 5N Plus inc, Sn-58Bi alloy, solid phase line temperature 138) having an average particle diameter of 30 μm, and an anisotropic conductive film (ACF-D). ) Was prepared.

Butadiene-acrylonitrile rubber, hydroxyl group-containing acrylic rubber, and a microcapsule type amine-based curing agent were mixed with a phenoxy resin and a liquid epoxy resin dissolved in PMA (propylene glycol monomethyl ether acetate). After the solder particles are dispersed in this mixed solution, it is coated on a PET (polyethylene terephthalate) film so that the thickness after solvent drying with a gap coater is +5 μm of the average particle size of the solder particles, and is anisotropic. A conductive film (ACF-D) was produced. Drying was carried out under the condition of 70 ° C.-5 min.

<Example 1>
A board-to-board connector for the plug and receptacle (Hirose Co., Ltd., BM23FR 0.6-20DS / DP) was prepared. There was a step (waviness) of about 20 μm on the bottom surface of the connector. Then, as shown in FIGS. 2 to 4, for each of the plug and receptacle connectors, the lead terminals extending toward the outside of the connector were bent toward the bottom surface of the connector to make the heights of the terminal surfaces uniform. The minimum height (distance) between the terminal surface and the bottom surface of the connector was 50 μm. Further, as shown in FIGS. 2 and 3, the reinforcing portion of each of the plug and receptacle connectors was scraped off.

In addition, a flexible printed circuit board (Dexerials Co., Ltd. evaluation FPC, Ni-Au plating) corresponding to the above plug and a rigid substrate (Dexerials evaluation glass epoxy board, 18 μm thick Cu pattern, Ni-Au plating) corresponding to the above receptacle. ) And prepared.

The plugs were aligned on a flexible substrate via an anisotropic conductive film and fixed at unweighted-room temperature. Further, the receptacle was aligned on the rigid substrate via an anisotropic conductive film and fixed at unloaded-room temperature. Then, by reflow, the plug was mounted on the flexible substrate, the receptacle was mounted on the rigid substrate, and the plug mounting body sample and the mounting body sample of Example 1 of the receptacle were prepared. The reflow conditions were 150 ° C. to 260 ° C.-100 sec, and the peak top was 260 ° C. Table 2 shows the initial continuity evaluation results of the plug mounting body sample and the receptacle mounting body sample, and the continuity evaluation results after the insertion / removal test.

<Example 2>
A plug mounting sample and a receptacle mounting sample of Example 2 were prepared in the same manner as in Example 1 except that ACF-B was used as the anisotropic conductive film. Table 2 shows the initial continuity evaluation results of the plug mounting body sample and the receptacle mounting body sample, and the continuity evaluation results after the insertion / removal test.

<Example 3>
A plug mounting sample and a receptacle mounting sample of Example 3 were prepared in the same manner as in Example 1 except that ACF-C was used as the anisotropic conductive film. Table 2 shows the initial continuity evaluation results of the plug mounting body sample and the receptacle mounting body sample, and the continuity evaluation results after the insertion / removal test.

<Comparative example 1>
A plug mounting sample and a receptacle mounting sample of Comparative Example 1 were prepared in the same manner as in Example 1 except that ACF-D was used as the anisotropic conductive film. Table 2 shows the initial continuity evaluation results of the plug mounting body sample and the receptacle mounting body sample, and the continuity evaluation results after the insertion / removal test.

<Comparative example 2>
ACF-B was prepared as an anisotropic conductive film.

A board-to-board connector for the plug and receptacle (Hirose Co., Ltd., BM23FR 0.6-20DS / DP) was prepared. There was a step (waviness) of about 20 μm on the bottom surface of the connector. The lead terminals and reinforcements extending outward from the plug and receptacle connectors were left untouched.

In addition, a flexible printed circuit board (Dexerials Co., Ltd. evaluation FPC, Ni-Au plating) corresponding to the above plug and a rigid substrate (Dexerials evaluation glass epoxy board, Ni-Au plating) corresponding to the above receptacle are prepared. bottom.

The plugs were aligned on a flexible substrate via an anisotropic conductive film and fixed at unweighted-room temperature. Further, the receptacle was aligned on the rigid substrate via an anisotropic conductive film and fixed at unloaded-room temperature. Then, by reflow, the plug was mounted on the flexible substrate, the receptacle was mounted on the rigid substrate, and a mounting sample of the plug and a mounting sample of Comparative Example 2 of the receptacle were prepared. The reflow conditions were 150 ° C. to 260 ° C.-100 sec, and the peak top was 260 ° C. Table 2 shows the initial continuity evaluation results of the plug mounting body sample and the receptacle mounting body sample, and the continuity evaluation results after the insertion / removal test.

<Comparative example 3>
A plug mounting sample and a receptacle mounting sample of Comparative Example 3 were prepared in the same manner as in Comparative Example 2 except that ACF-C was used as the anisotropic conductive film. Table 2 shows the initial continuity evaluation results of the plug mounting body sample and the receptacle mounting body sample, and the continuity evaluation results after the insertion / removal test.

<Comparative example 4>
A plug mounting sample and a receptacle mounting sample of Comparative Example 4 were prepared in the same manner as in Comparative Example 2 except that ACF-D was used as the anisotropic conductive film. Table 2 shows the initial continuity evaluation results of the plug mounting body sample and the receptacle mounting body sample, and the continuity evaluation results after the insertion / removal test.

Since the ACF-D used in Comparative Example 1 and Comparative Example 4 is for thermocompression bonding and does not contain a flux compound, the initial continuity of the plug mounting body sample and the receptacle mounting body sample cannot be obtained. , Could not connect. The board-to-board connectors of the plugs and receptacles used in Comparative Examples 2 and 3 required a large mounting surface because the lead terminals extended outward. Further, the plug-to-board connector of the plug and the receptacle used in Comparative Example 2 and Comparative Example 3 could not be connected due to the step on the bottom surface of the connector.

On the other hand, the board-to-board connector of the plug and receptacle used in Examples 1 to 3 has a terminal row on the bottom surface of the connector, absorbs a step on the bottom surface of the connector, and the anisotropic conductive film forms a solder particle. Since it contains a flux compound, it can be connected. Therefore, the terminal row can be made fine pitch, and the connector can be miniaturized.

The receptacles used in Examples 1 to 3 have a connection area of 120 μm × 170 μm and L (Line) / S (Space) = 120 μm / 230 μm, but by using solder particles having an average particle diameter of 10 μm, In principle, it is possible to make a fine pitch up ^{to a connection area of 10000 μm 2} (50 μm × 200 μm) with an L / S of 50 μm / 50 μm and a line length of 200 μm.

10 Substrate, 11 1st Terminal Row, 20 Connector, 21 2nd Terminal Row, 30 Thermocurable Connecting Material, 31 Solder Particles, 32 Solder Bonding, 33 Thermocurable Connecting Material, 40 Plugs, 41A 1st Male Mold Vertical Fitting Row, 41B Second Male Mold Vertical Fitting Row, 42A First Terminal Row, 42B Second Terminal Row, 43 Insulating Resin, 50 Receptacle, 51A First Female Mold Vertical Fitting Row, 51B second female vertical mating row, 52A first terminal row, 52B second terminal row, 53 insulating resin, 60 tools, 71 first FPC, 72 second FPC, 81a, 82a Connection part, 81b, 82b male type vertical fitting part, 83a, 84a connection part, 83b, 84b male type vertical fitting part, 85a, 86a connection part, 85b, 86b male type vertical fitting part, 87a, 88a connection part , 87b, 88b male vertical fitting part, 91a, 92a connecting part, 91b, 92b vertical part, 91c, 92c female vertical fitting part, 93a, 94a vertical part, 93b, 94b connecting part, 93c, 94c female type Vertical Fitting, 140 Plugs, 141A First Male Vertical Fitting Row, 141B Second Male Vertical Fitting Row, 142A First Lead Terminal Row, 142B Second Lead Terminal Row, 143 Insulation Resin, 150 receptacle, 151A first female vertical fitting row, 151B second female vertical fitting row, 152A first lead terminal row, 152B second lead terminal row, 153 insulating resin.

Claims (15)

A substrate having a first terminal row and
A connector with a second row of terminals and
It is provided with an adhesive layer in which a thermosetting connecting material for connecting the first terminal row and the second terminal row is cured.
The second terminal row is arranged on the bottom surface of the connector to form a step absorbing portion that absorbs the step on the bottom surface.
A connector in which the thermosetting connecting material contains solder particles and a flux component. The bottom surface of the connector has a step with a height within a predetermined range.
The connector according to claim 1, wherein the difference between the maximum value and the minimum value of the height of the terminal surface in the second terminal row is smaller than the height in the predetermined range. The connector according to claim 1 or 2, wherein the difference between the maximum value and the minimum value of the height of the terminal surface in the second terminal row is smaller than the average particle size of the solder particles. The connector according to claim 1 to 3, wherein the second terminal row extends from the outside to the inside of the bottom surface of the connector. The connector according to claim 1 to 4, wherein the average particle size of the solder particles is 30 μm or less. The connector according to claim 1 to 5, wherein the minimum distance between terminals in the second terminal row is 0.8 mm or less. The connector according to claim 1 to 6, wherein the connector does not have a reinforcing portion. A connector used for the connector according to claims 1 to 7. A thermosetting connecting material used for the connecting body according to any one of claims 1 to 7. A second terminal row is arranged on the bottom surface of the substrate having the first terminal row via a thermosetting connector material containing solder particles and a flux component, and a step absorbing portion that absorbs the step on the bottom surface. Place the formed connector,
Manufacture of a connector in which the thermosetting connection material is thermoset at a temperature equal to or higher than the melting point of the solder particles without pressing the connector to connect the first terminal row and the second terminal row. Method. The method for manufacturing a connector according to claim 10, wherein the thermosetting is performed by reflow. The method for producing a connector according to claim 10 or 11, wherein the average particle size of the solder particles is 30 μm or less. The method for manufacturing a connector according to claims 10 to 12, wherein the minimum distance between terminals in the second terminal row is 0.8 mm or less. It has a terminal row arranged on the bottom surface with a step of a predetermined height.
A connector in which the difference between the maximum value and the minimum value of the height of the terminal surface in the terminal row is smaller than the height of the step. The connector according to claim 14, wherein the terminal row extends from the outside to the inside of the bottom surface of the connector.

Images