JPH0566037B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (1) TECHNICAL FIELD OF THE INVENTION The present invention relates to electrical connection devices and, more particularly, for making relatively large numbers of separable interconnections in a relatively small space with zero insertion force and zero insertion force. Connecting devices that can be used in a state close to the pulling force and that maintain the connection by themselves after connection, or for electrically interconnecting electrical devices such as LSI modules, IC modules, circuit boards, etc. Relating to a device, i.e., a connector.

(2) Prior art and problems Conventional electrical connection devices usually consist of a pin (contact pin) corresponding to a male contact and a jack corresponding to a female contact. They are designed to connect with each other. The jack is equipped with a spring mechanism capable of applying a significant contact force to the contact pin to ensure stability of contact with the contact pin. However, since this spring mechanism works and a fairly strong contact force is applied to all contact pins, the insertion force when inserting the contact pin into the jack or the removal force when removing the contact pin from the jack can be ignored. It grows to such an extent that it doesn't. In fact, the insertion and removal forces of contact pins increase as the number of contact pins per unit connection device increases, and when the number of contact pins is on the order of several hundred, insertion force of several tens of kilograms or more Power is required. In this case, it is no longer possible to operate the connecting device manually, and it is essential to insert and remove the pins using jigs.

Further, in the conventional connection device as described above, when a large pin insertion and removal force is applied during connection and removal, the electrical device is often undesirably damaged. Furthermore, in such a connecting device, it is necessary to provide its constituent members with sufficient strength to withstand large pin insertion and removal forces, and as a result, the device itself is forced to increase in size. .

Recently, attempts have been made to reduce the pin insertion and removal forces in response to the increase in the number of pins per connection device. For example, they are known as zero insertion force (ZIF) and light insertion force (LIF) connections. There are connection devices that use a cam mechanism to apply contact force after the contact pin is inserted into the jack, or connection devices that use a slide cam to connect in parts rather than all at once, and others. That's it. However, these connection devices require complicated mechanisms and
This requires complicated handling and also causes an increase in manufacturing costs.

Conventional electrical connection devices for connecting LSI modules to circuit boards generally consist of contact pins protruding from the bottom of each LSI module and a circuit board jack into which the contact pins can be inserted. Additionally, the jack of the circuit board is provided with a spring mechanism of some configuration for applying a fairly strong contact force to the contact pins. However, when using such a connection device, as with the connection device described above, as the number of contact pins on the module increases, a greater pin insertion force is required, making practical operation impossible. .

This type of connection also requires considerably more space than is intended because the jack has a certain shape of spring mechanism. Such an increase in space is generally a limiting factor in the number of contact pins that can be provided on a module or the like, which makes it impossible to obtain an electrical connection device with a high density of contact pins.

Further, from JP-A No. 56-59480, there is provided a wiring supported by a base material, a low melting point metal, and a heating means for melting the low melting point metal, and the low melting point metal is melted by the heating means. A connector configured to be connected to the wiring when the wire is connected is known. This connector is provided with heating means on its surface, and also has a recess formed therein for accommodating the low melting point metal. However, this connector is suitable for electrical connection when wiring is provided on the inner wall or bottom wall of the board recess, and cannot be used for connecting wiring (circuit pattern) provided on the surface of the board.

Furthermore, from Japanese Patent Application Laid-Open No. 57-20500, a connector for electrically connecting pins of a wiring board, etc., has an abacus-shaped socket for accommodating a fluid conductor (particularly mercury). Boards are known. This connector plate utilizes the phenomenon in which mercury solidifies at extremely low temperatures, so that it is possible to obtain the desired electrical connection when using the electronic circuit module. This connector plate, however, remains problematic in retaining mercury within the socket and in non-cryogenic applications.

(3) Object of the invention The object of the invention is to provide an improved electrical connection device which overcomes the above-mentioned disadvantages, in other words it can be assembled and removed with very low pin insertion and removal forces. is easily possible,
It is possible to make high-quality connections with multiple contacts, it is possible to connect a large number of electrically independent contacts with high density in a relatively small space, the assembly cost is low, and the electrical connection is highly reliable. The object of the present invention is to provide an entirely new type of electrical connection device with which interconnections can be obtained.

(4) Structure of the Invention The present invention, in one aspect, is a device for electrically connecting contact pins to each other by interposing them between electrical devices, and comprising: a connection board made of an insulating material; a guide hole with a constant inner diameter drilled through the connection board into which a contact pin of an electrical device can be inserted; a cylindrical metal reservoir formed approximately in the center of the guide hole; housed in the metal reservoir; A combination of: a low melting point metal with a melting point of 100 to 170°C used for connection between contacts, and a heating element for melting the low melting point metal disposed inside the connection board and near the metal reservoir. An electrical connection device comprising:

Moreover, in another aspect of the present invention,
A device that is interposed between electrical devices to electrically connect the contact pins of one electrical device and the circuit pattern on the surface of the other electrical device, comprising: a connection board made of an insulating material; a guide hole with a constant inner diameter into which a contact pin of an electrical device can be inserted; a metal reservoir having a cross section that can be expanded into a funnel shape, a low melting point metal with a melting point of 100 to 170°C, which is used for connection between contacts, housed in the metal reservoir, and inside the connection board and in the vicinity of the metal reservoir. A heating element for melting the low melting point metal, which is disposed in the electrical connection device.

Furthermore, another aspect of the present invention is a device for electrically connecting a contact pin of one electrical device and a circuit pattern on a surface of the other electrical device by interposing the device between the electrical devices. , a connection board made of an insulating material, a guide hole drilled through the connection board and having a constant inner diameter into which a contact pin of an electrical device can be inserted, and an end of the guide hole on the side facing the circuit pattern. a metal reservoir formed at the end and having a tapered cross section toward the surface of the connection board; a low melting point metal with a melting point of 100 to 170° C. housed in the metal reservoir and used for contact-to-contact connection; and the connection. An electrical connection device characterized in that it includes a heating element for melting the low melting point metal, which is disposed inside the board and near the metal reservoir.

As can be understood from the above, the electrical connection device of the present invention places the connection board made of an insulating material at a position corresponding to the contact pins, wiring patterns, etc. of the electrical device to be connected. A pore is drilled through it into which the pin to be connected can be inserted, and a metal reservoir is placed anywhere inside this pore for pooling a low melting point metal (used for connection between contacts of electrical equipment). The purpose is to achieve the desired contact connection by melting and solidifying the low melting point metal pooled in the metal reservoir by operating the attached heating element.

To make a contact connection, the contacts of the electrical device to be connected (at least one of them in the form of a contact pin) must be aligned oppositely at the connection point on the connection board and placed in the vicinity of the metal reservoir. First, the connection board is heated by passing a current through the heating element, and then the low melting point metal in the metal reservoir is melted by the heat transfer effect, and in this state,
Lightly press down on the electrical device to be connected, such as a module, to which a contact pin is attached, and insert the contact pin into the connection board.With the pin still inserted, the power to the heating element is cut off, reducing the temperature of the connection board. , thus solidifying the low melting point metal in the metal reservoir. In this way, a reliable, low contact resistance connection can be obtained.

When disconnecting the contact, the connection board is heated by energizing the heating element as in the case of connection, and the contact pin is removed after the low melting point metal is melted.
In this way, the contact connection can be broken with only a very weak force.

The force required to make and release contact connections using the electrical connection device of the present invention is very small and due to the fact that the contact pins are mated with molten metal. , since it is close to a no-load state, even if the number of contact pins is on the order of several thousand, it is substantially equivalent to a no-load state. Furthermore, since the part corresponding to the jack in the conventional connection device is made by melting and solidifying a low-melting point metal, the spring mechanism attached to the jack is not required, and therefore the space per contact pin (occupied area ) is reduced dramatically to a maximum of 2 mm ² . As a result, a large number of contact points can be provided in a relatively small area.

When implementing the present invention, alumina, forsterite, mullite,
or glass-ceramic materials that are composite materials of glass such as borosilicate glass and ceramic such as alumina, or ceramic materials that can be processed by ordinary machining (Macol; a trade name of Corning Corporation in the United States); Furthermore, photosensitive glass ceramic materials such as Photoceram (trade name of Corning Incorporated) can be advantageously used. In some cases, when ease of processing and manufacturing such as drilling and embedding heating elements is desired, heat-resistant resin materials such as polybutadiene, polyimide, and other materials are used in place of ceramic materials. be able to.

The guide hole drilled in the connection board needs to have a size that allows insertion of the contact pin of the electrical device. This guide hole usually has a cylindrical shape with a constant inner diameter over its entire length, and a metal reservoir is provided approximately at the center or at one end.
Further, it is desirable that the end of this guide hole is chamfered. The guide holes in the connection board are formed according to conventional methods, such as laser machining, electron beam machining, or ultrasonic machining for ceramic materials, drilling for machinable ceramic materials, and drilling for resin materials. can be done.

As described above, it is essential that the guide hole bored in the connection board be provided with a metal reservoir. When electrically connecting contact pins,
It is recommended to form a cylindrical metal reservoir approximately in the center of the guide hole. This is because, in the case of a cylindrical shape, not only can the low melting point alloy be held easily and reliably, but also drilling can be easily performed according to a conventional method. In addition, when electrically connecting a contact pin and another contact such as a circuit pattern, the end of the guide hole facing the circuit pattern etc. should be placed facing the surface of the connection board. It is recommended to form a metal reservoir with a funnel-shaped enlarged cross section. If the metal reservoir is funnel-shaped like this, it will be connected directly to the circuit board side using a low melting point alloy, so the signal propagation distance can be shortened compared to the case where it is connected using a contact pin. Therefore, it is advantageous for high-speed transmission of pulse signals. This makes it possible to achieve even higher speeds of the system. Furthermore, since the expanded portion is filled with a low melting point alloy, there are advantages such as relatively easy filling of the low melting point alloy. Furthermore, when electrically connecting a contact pin and another contact such as a circuit pattern, the end of the guide hole facing the circuit pattern etc. should be It is also recommended to form the metal reservoir once with a tapered cross section. If the metal reservoir has a tapered shape like this,
Since it is directly connected to the circuit board side using a low melting point alloy, the signal propagation distance can be shortened compared to the case where it is connected using a contact pin. Therefore, it is advantageous for high-speed transmission of pulse signals. This makes it possible to achieve even higher speeds of the system.
Also, since it is tapered, the area (size) required for one connection can be reduced. As a result,
The spacing between adjacent connections is increased, greatly reducing the risk of shoots and improving reliability. Furthermore, when a low melting point alloy is melted, it is easier to prevent the melt from flowing out compared to a funnel-shaped metal reservoir.

Guide holes for contact pin insertion can be made as necessary.
Its inner surface can be coated with a metallic material. This is very effective in making it easier to fill the guide hole and the metal reservoir with the low melting point metal and to hold it there. The metal material used here is not particularly limited as long as the material has adhesion to the ceramic material or resin material of the connection board. Preferred metal materials include, for example, Pd-Ag alloy, Pd-Au alloy, Pt-
Au alloy, Au, Ag, Cu, etc. These materials can be uniformly coated on the inner surface of the guide hole by using techniques commonly used in this technical field for forming thick films, for example when the connection board is made of ceramic material. The thickness of this metal coating is preferably from several μm to several tens of μm.

According to the present invention, the surface of the connection board that is in contact with the module can be coated with an insulating resin material having low thermal conductivity. This resin material coating is
When the connection board is made of ceramic material such as an alumina plate, it is effective for increasing the heat generation effect of the heating element built into the connection board and suppressing the influence of heat from the heating element on the module (insulation effect). It is. Of course, the thermal conductivity of this coating is
It must be at least smaller than that of the connection board. Preferred resin materials that can be used here are, for example, polybutadiene, polyimide, and the like. These materials can be coated on the surface of the connection board by a conventional method, such as a bar coating method or a doctor blade method.
The thickness of this resin coating is preferably several μm to
It is 100μm.

When operating the apparatus in the present invention under normal conditions, all useful low melting point compounds are preferably 100
It has a melting point of ~170°C. Examples of such metals include In-Sn alloy, Bi-Sn alloy, and Bi-Sn alloy.
Pb alloy, rose alloy (consisting of Sn, Bi, Pb),
Others may be used advantageously. If the melting point of the low-melting point metal is 100°C or lower, there is a risk that the metal will melt during operation of the electrical device, causing a connection failure. This is because when the device is used in its normal state, the heat generated by the LSI element causes the temperature of the module on which the element is mounted to rise, and the temperature of the adjacent connection board to rise as well. On the other hand, if the melting point of a low-melting point metal is excessively high, it is necessary to increase the temperature to melt it.
As a result, the temperature of the connection board containing a low-melting point metal will inevitably rise. This has an adverse effect on printed circuit boards placed in the vicinity of the connection board. In other words, circuits on printed circuit boards are usually formed with a 60Sn-40Pb solder film, and the melting point of this solder material is approximately
Since the temperature is 180°C, if the temperature of the connection board exceeds this temperature, the solder plated film may be affected by heat. Furthermore, even if the printed circuit board is made of a material such as polyimide that has excellent heat resistance, it is inevitable that the printed circuit board will also be affected by heat. For the above reasons, the preferable melting point range of the low melting point metal according to the present invention is defined as described above. However, this melting point range is currently specified for equipment used under normal conditions, and for example where modules, circuit boards, etc. are immersion liquid cooled, or where printed circuit boards and If the thermal constraints on the solder-plated film are changed, the preferred melting point range of the low melting point metal is not limited to the range stated above. Furthermore, since the melting point of the metal is within the above range, it is advantageous from the standpoint of the heating element used in combination.

As mentioned above, a heating element for melting the low melting point metal is essential in the present invention. The heating element is not particularly limited as long as it does not adversely affect the connection device of the present invention and effectively heats the connection board and melts the low melting point metal. Examples include using a thick-film, thin-film resistor and wiring it inside the connection board, or using a thick-film, thin-film resistor and forming it on the surface of the connection board, which is then further layered with an insulating layer. It can be used as a heating element by coating it with Nichrome and the like are commonly used as resistance materials, but are not particularly limited. The latter configuration is advantageous when the intention is to reduce the number of man-hours, and in that case, the shape, number, position, etc. of the heating elements to be formed do not matter at all as long as they are placed near the metal reservoir. Not done.

If necessary, a metal layer for a heat sink can be formed near the metal reservoir. Formation of such a metal layer is effective in concentrating the heat from the heating element around the metal reservoir without conducting it uniformly to the surroundings, and thus increasing the efficiency of melting the low melting point metal in that area. The shape of such a metal layer is not limited, but it will be appreciated that it is advantageous to form it so that it surrounds a metal reservoir. Metal materials useful for forming such metal layers include:
For example, Au, Ag, Cu, etc. When conventional methods such as thick film formation, sputtering, and vacuum evaporation are applied to such metal materials,
The desired metal layer can be formed technically easily.

(5) Embodiments of the invention Next, embodiments of the invention will be described with reference to the attached drawings. However, since these examples merely show preferred examples of the present invention,
It should be understood that various modifications and improvements may be made within the scope of the invention. It should also be understood that the same members are numbered the same in the figures.

FIG. 1 is an enlarged cross-sectional view of a portion of the connection device of the present invention that serves as one connection point. 1 in the figure indicates a connection board made of alumina, which is an electrical insulator. A guide hole 2 is bored through the connection board 1 into which a contact pin (not shown) is inserted. Both ends of the guide hole 2 are chamfered, as indicated by 2', to allow smooth insertion of the contact pin.

The chamfering of the end of the guide hole not only facilitates insertion and removal of the contact pin, but also greatly reduces defects such as bending of the pin when inserting the contact pin. A metal reservoir 3 is formed in the center of the hole 2, and a low melting point metal 4 is pooled in the metal reservoir 3. A heating element 5 is formed around the metal reservoir 4 so as to surround it. 6 is a terminal for supplying electricity to the heating element.

In the illustrated example, the heating element is wired in a state where it is completely enclosed inside the connection board. The heating element used was a thick film paste (resistance paste No. 4720 manufactured by EI Dupont) with a sheet resistance of 100 Ω/sq. Further, an In-48%Sn eutectic alloy (melting point: 117°C) was used as a low melting point metal, and an appropriate amount of this alloy was injected into the metal reservoir of the guide hole to fabricate the electrical connection device of the present invention. The diameter of the guide hole for inserting the contact pin was 0.5 mm, and the thickness of the connection board was 2 mm.

FIG. 2 is a partially enlarged sectional view showing a state in which two electrical devices (not shown) are connected via their respective contact pins using the connecting device of the present invention shown in FIG. . Contact pins are 11 and 12
and are fixedly supported by insulating contact pin supports 13 and 14, respectively. The tips of the contact pins 11 and 12 are embedded in the solidified bottom melting point metal 4 that completely fills the metal reservoir 3. The contact pin supports 13 and 14 are respectively formed with stoppers 15 and 16 at several locations (only one location is illustrated in FIG. 2) for positioning the contact pins. A member 17 provided through the connecting device 10 and the contact pin supports 13 and 14 is a pin for lateral positioning when connecting these members.
In the example shown, the diameter of the contact pin used is
It was 0.3mm. In this example, for convenience, the thickness is 5 μm.
Phosphor bronze wire (diameter 0.3 mm) with Sn plating was used.

In order to form the electrical connection device shown in FIG. were positioned correctly, and the contact pins 11 and 12 were inserted until their tips reached the guide hole 2. In this state, power is applied to the heating element 5 from the terminal 6 to connect the connection board 1.
was heated, and subsequently, the low melting point metal 4 was melted by the heat transfer effect in this board. after that,
The contact pin was further inserted into the guide hole and stopped when the stoppers 15 and 16 came into contact with the surface of the connection board. Contact pins were buried in molten metal. While the contact pin was buried in the molten metal, electricity to the heating element was stopped to solidify the metal. Through these steps, the contact pins can be brought into sufficient contact through the low melting point metal due to diffusion between the low melting point metal and the contact pin and contraction when the low melting point metal solidifies, and thus, An excellent contact connector was obtained. The contact resistance at this time was 1 mΩ or less and stable. Note that when the low melting point metal was melted, it was pooled in the metal reservoir due to surface tension and did not flow out of the guide hole.

Next is the procedure for disconnecting the contact pins, which can be done by performing the opposite operation to the above-described connection procedure. That is, after the low melting point metal is melted again, the contact pin is removed from there, and the low melting point metal is cooled until it solidifies again and returns to its original state. Although the inventors repeated connecting and disconnecting the contact pin many times, no change was observed in the resulting contact resistance (contact resistance <1 m
Ω).

Next, a typical example in which the connecting device of the present invention is used to connect an electrical device with multiple contact pins will be explained with reference to the attached FIG. 3 and subsequent figures.

FIG. 3 is a plan view of a printed circuit board to which a plurality of LSI modules are attached to which the present invention can be applied. The printed circuit board is 20 in the figure.
, and LSI modules 21, 22, and 23 are attached. Each of these LSI modules is equipped with a plurality of LSI chips, as indicated by t in the module 21. In the figure, 24 represents a place where the fourth LSI module is to be installed, 25 represents a circuit pattern on the surface of the circuit board 20, and 26 represents a through hole for a guide pin. The circuit board 20 further includes contacts 2 for contacting contact pins of a card edge connector or the like.
7 is also printed.

As LSI modules become highly integrated, hundreds of terminals or contact pins are attached to the bottom or side surfaces of the modules, and it becomes necessary to connect these terminals or pins to a printed circuit board. By using the connecting device of the present invention, it is possible to reliably connect such multiple contact pins with near zero insertion force and zero removal force. That is,
If the connecting device of the present invention as shown in FIG. 4 is interposed between the LSI module and the printed circuit board as shown in FIGS. 5 and 6, a stable electrical connection can be achieved. The connecting body can be obtained relatively easily.

FIG. 4 is an enlarged cross-sectional view of a portion serving as one connection point of the connection device of the present invention for connecting an LSI module having a large number of contact pins and a printed circuit board. The shape of this device is basically the same as that shown in FIG. 1, except that the metal reservoir 3 has been moved to the lower end of the guide hole 2 and its shape has become funnel-like.

Fig. 5 is an enlarged cross-sectional view of a part of the electrical connection device when the connection device shown in Fig. 4 is sandwiched between an LSI module and a printed circuit board to form an electrical connection device. be. As the contact pin 31 attached to the LSI module 21, here, a phosphor bronze wire (0.3 mm in diameter) coated with Sn and having a thickness of 5 μm was used. The procedure for connecting the LGI module 21 to the printed circuit board 20 was as follows: Align and place the connection board 1 above the circuit board 20, and then connect the LSI module 2 to it.
Align 1. After alignment, the contact pin 31 of the module 21 is inserted into the end of the guide hole 2, and in this state, the heating element 2 is energized. When the low melting point metal 4 is melted, the contact pin 31 that was previously guided to the entrance of the guide hole 2 is inserted further in, and the stopper (not shown, 32 in FIG. 6) is inserted into the connection board 1. The pin 31 is brought into contact with the molten low melting point metal 4 by inserting it until it contacts the surface. Meanwhile, at the same time, the low melting point metal 4 is transferred to the metal reservoir 3
It forms a convex liquid surface downward due to its own weight, and is securely connected to the circuit pattern 25, which is another connected member. Thereafter, the power to the heating element is cut off, and the low melting point metal is solidified in that state. In this way, a stable electrical connection between the LSI module and the circuit board was obtained. The contact resistance at this time was 1 mΩ or less.
This is the separation of the electrical connection that was formed.
This can be easily achieved by carrying out the above procedure in reverse order.

FIG. 6 is a schematic cross-sectional view showing a configuration in which an LSI module and a printed circuit board are connected through the electrical connection device of the present invention through connection of a large number of contact pins. For example, LSI module 21
In this case, contact pins 31 are installed in a predetermined area (40×40 mm) at intervals of 1.27 mm, and there are 900 contact pins in total. These contact pins are each insulated and have annular pads 36 as shown. The annular pad 36 is fused to the bottom surface of the LSI module. Guide holes 2 are provided in the connection board 1 to correspond to the contact pins arranged in alignment on this LSI module, and circuit patterns 25 of the printed circuit board 20 are provided at positions corresponding to these guide holes. and 28 are arranged in line.

Printed circuit board 20 is a multilayer printed circuit board. Reference numerals 29 in the figure represent copper foils constituting the circuit, and each of them is completely independent due to the insulating material of the board 20. Each copper foil layer 29
are through-hole plating layer 34 and plating layer 35
The circuit patterns 25 and 28 on the substrate surface are
It is connected to the.

In this way, a large number of contact pins 31, guide holes 2, and circuit patterns 25 and 28 are connected to the stopper 3 attached to the LSI module 21.
The position is determined by the guide pins 33 with two guide holes 7 of the connection board 1 and the guide holes 26 of the printed circuit board 20.

As is clear from the above explanation, when the connection device of the present invention is used, an LSI module having a large number of contact pins as shown in FIG. 6 can be connected via a connection board by the method shown in FIG. Can be connected to a circuit board. This connection is made with the low-melting point metal molten, so even if there are as many as 900 pins in high density, virtually no force is required when inserting the pins. It is. In addition, since this connection is a type of diffusion connection, very stable and low contact resistance can be obtained, and the contact is self-maintained by itself after connection.In particular, it is not necessary to provide means such as external tightening. does not require.

Furthermore, in the connection device shown in FIG. 4, polyimide resin was used instead of alumina as the material for the connection board 1, and contact connections were made as shown in FIGS. 5 and 6. As described below, polyimide resin has sufficient heat resistance to withstand solder immersion at 260°C for 60 seconds.
This is what was chosen here. In general, as long as the resin material has sufficient electrical insulation and heat resistance, it can be made by appropriately selecting the low melting point metal used and its melting conditions.
It can be used as a connection board by taking advantage of its features. In this example, in addition to using polyimide resin as the insulating material, a rolled nichrome alloy (thickness: 50 μm) was used as the heating element 5. To manufacture the connection board with the heating element, we directly applied the manufacturing method of multilayer printed circuit boards that is commonly used in this field. In the case of this example, it was very easy to form the guide hole in the connection board and to stack and adhere the resin plates for incorporating the heating element.

In FIG. 7, a portion of the connection device of the present invention, which serves as one connection point, is shown in an enlarged scale. This connecting device 10 is similar to that shown in FIGS. 1 and 4, except that the tip of the guide hole 2 is tapered.
It is basically constructed based on the same concept as the connecting device shown in the figure. The manner in which the guide hole 2 tapers is not particularly limited as long as that portion can function as the metal reservoir 3. In this example as well, the electrical connection device can be constructed using the same materials, dimensions, etc. as those used in FIGS. 1 and 4 above.

In FIG. 8, an example of a contact pin that can be used in the connection device of FIG. 7 is shown at a glance. 21 in the figure represents an LSI module, to which a tapered contact pin 31 is attached as shown. The tip b of the contact pin is slightly smaller than the tip a of the guide hole 2.

Figure 9 is an enlarged cross-section of a portion of the connection device shown in Figure 7, which is inserted between an LSI module and a printed circuit board to form an electrical connection. It is shown as follows. The printed circuit board 20 is generally a multilayer printed circuit board, but here, for convenience,
The case of a single layer circuit is shown. The circuit (here, the copper foil layer) 29 is formed by the plating layer 35,
It is connected to the circuit pattern 28. The state after the low melting point metal 4 is melted and the contact pin 31 and the circuit pattern 28 are brought into contact and solidified again, thus connecting the contact pin and the circuit pattern is shown. As is clear from this figure,
The contact pin 31 preferably has a length such that when the LSI module and the connection board are assembled, the tip of the contact pin is flush with the tip of the narrow guide hole of the connection board.

The illustrated electrical connections can be made and removed in a manner similar to that previously described with reference to FIG. The results obtained were similarly good, and experiments showed that the contact resistance was less than 1 mΩ.

In this example, contact pin 3 is connected to LSI module 21.
1 are arranged in a predetermined area of 40 x 40 mm in a total of 1,600 pieces at intervals of 1.0 mm in an insulated state. The contact pin 31 has a diameter of 0.3 mm and an annular pad 3 with a diameter of 0.5 mm.
6. The annular pad 36 is fused to the lower surface of the LSI module 21. Guide holes are provided on the connection board to correspond to the contact pins arranged in alignment on this LSI module, and circuit patterns 28 are provided on the top surface of the printed circuit board to correspond to the guide holes. It is provided. It is obvious that the density of the connection body shown here is much greater than that of the connection body with 900 contact pins described above.

FIG. 10 is a partially enlarged sectional view showing another preferred embodiment of the electrical connection device of the present invention, in which a metal atmosphere is formed on the inner surface of the guide hole. The illustrated connecting device is essentially the same as that of FIG. 4, except that a metallization is provided. That is, the board 1 of the connecting device 10 has a guide hole 2 for inserting a contact pin, a funnel-shaped metal reservoir 3 formed at the lower end of the guide hole, and a low melting point metal 4 pooled in the metal reservoir. and a heating element 5 (connected to the terminal 6) for melting the metal, and a Pd-Ag alloy coating layer 37 with a thickness of approximately 5 μm is installed on the inner surface of the guide hole (chamfered). (including the inner surface of the portion 2').

FIG. 11 is a partially enlarged cross-section showing another preferred embodiment of the electrical connection device of the present invention, in which the surface of the connection board in contact with the module is coated with a low-conductivity insulating resin material. It is a diagram. The illustrated connecting device is basically the same as that shown in FIG. 4, except that it is further coated with an insulating resin material as described above (for details, please refer to the description of FIG. 4). . In this example, as shown in the figure, the surface of the connection board 1 on the side that contacts the module (not shown) is made of polyimide resin 3 with a thickness of approximately 50 μm.
It is covered with 8. As a result of providing a layer with low thermal conductivity between the module and the connection board in this way, it is possible to prevent heat from flowing to that side, which has a negative effect on the module, and to reduce heat inside the connection board, especially around the metal reservoir. can be achieved with the accumulation of

According to the present invention, the heating element, ie, the resistor, can be formed at any position and in any pattern within the connection board. Specific examples of these patterns are shown in FIGS. 12, 13a, and 14a. In the figure, 2 represents a guide hole, 5 represents a heating element, and 40 represents a conductor. First, the formation of the heating element pattern will be explained with reference to FIG.
Drill 30 x 30 pores with a diameter of 0.5 mm using the same pitch. For drilling, laser machining or ultrasonic machining techniques can be used. Another perforation method that can be used is to first perforate the alumina substrate in a green sheet state before sintering, and then sinter the alumina substrate. On the alumina substrate thus prepared, a heating element (resistor) and a conductor connecting them are formed using a thick film screen technique. In the example shown, the dimensions of the heating element are 0.4mm wide
and the length was 1 mm. Since there are 30 holes (to become guide holes) per row in the longitudinal direction, 30 heating elements as shown in the figure are formed, and a conductor is formed to connect them in series. These series connected heating elements have a number of holes.
Since there are 30 pieces, 31 columns are formed in the horizontal direction of the figure. Next, the resistors in each column are connected in parallel using conductors. In this example, the heating element is
No. 4720 resistance paste manufactured by I-DuPont was used, and No. 9770 conductor paste manufactured by the same company was used as the conductor. Of course, other heating elements and conductive pastes may be used, and thin film techniques such as sputtering may also be applied. The resistance measured between the positive and negative electrodes of the heating element thus manufactured was approximately 250Ω. The substrate on which the heating element and conductor were formed and a separately prepared substrate having the same dimensions and similar guide holes were adhered to each other using 9137 paste manufactured by EI Dupont. Finally, as a test, a voltage of 60V was applied to the connection body of the two boards that had been glued together.
It was confirmed that the Sn alloy had melted.

Subsequently, Fig. 13a (Fig. 13b and Fig. 13)
When the heating element patterns as shown in Figure 14a (also Figure 14b) were formed, the first
The same effect as in Fig. 2 was obtained.

FIG. 15 shows a connection device in which a metal layer for a heat sink is formed around a metal reservoir. FIG. 16 is also similar to this. With this configuration, the heat generated by the heating element can be guided preferentially to the metal reservoir, thereby uniformly heating all the metal reservoirs of the connecting device, and making it possible to quickly melt the low-melting point metal. 15 shows an example in which the heat sink metal layer 8 is embedded in the connection device 10 shown in FIG. 1, and FIG. 16 shows an example in which the heat sink metal layer 8 is embedded in the connection device 10 shown in FIG. An example of how each is buried is shown.
In these examples, each of the metal layers 8 is formed of a thick Au film with a thickness of 10 μm in an annular shape surrounding the metal reservoir 3 .

As shown in FIGS. 17 and 18,
It is also possible to form the heating element 5 on the surface of the connection board 1. However, in this case, it is necessary to further cover the heating element 5 with an insulating layer 9. That is, it is important that the heating element 5 should not be exposed as it is on the surface of the connection board 1, but should be built into the connection board 1, although it has a special shape. In the illustrated example, there are 41 terminals for energizing the heating element.
, and a conductor path electrically connecting the terminals 41 is shown at 42. In this example, the heating element 5 is a thick film paste (resistance paste No. 4720 made by EI Dupont) with a sheet resistance of 100 Ω/sq, and the terminal 41 is a thick film conductor paste (conductor paste made by EI Dupont). No. 9770), and as the insulating layer 9, an insulating paste (insulating paste No. 9137 manufactured by EI Dupont) was used. Furthermore, in order to form the conductor path 42, a conductor paste (E-
A thick film method was carried out using conductor paste No. 9770 manufactured by I-Dupont. However, this conductor track can be formed by filling the entire hole drilled in the connection board 1 with a conductor, or by providing a conductor layer on the inner surface of the hole.

(6) Effects of the Invention According to the present invention, first, electrical devices can be connected and disconnected with very small insertion and removal forces. Additionally, the use of spring-loaded locks is unnecessary;
The area occupied by one contact pin can be significantly reduced, and therefore, within a relatively small area,
A large number of connections can be provided. Furthermore, according to the present invention, a highly reliable connection with low contact resistance can be achieved. Moreover, the electrical connection device of the present invention can be assembled at low cost.

According to the invention, the connecting device can be manufactured relatively easily, especially by forming the connecting board using a resin material. Furthermore, by changing the shape of the guide holes, higher density connections can be made. Furthermore, by coating the inner wall of the guide hole with a metal material, filling and retention of the low melting point metal can be made easier. In addition, by coating the surface of the connection board that comes into contact with the module with an insulating resin with low thermal conductivity, it is possible to prevent the influence of heat on the module and to enhance the heat dissipation effect within the connection board. can.

Further, according to the present invention, by forming a heat sink metal layer around the metal reservoir, the metal reservoir portion can be heated efficiently and in a short time, and all the metal reservoir portions of the connection device can be heated evenly. Can be heated. Further, according to the present invention, by positioning the heating element on the surface of the connection board, the number of man-hours required for forming the heating element can be reduced.

[Brief explanation of the drawing]

FIG. 1 is a partially enlarged sectional view showing a preferred embodiment of the electrical connection device of the present invention, and FIG.
3 is a cross-sectional view showing a state in which connections are made between contact pins using the connecting device shown in the figure. FIG. 3 is a plan view of a circuit board on which an LSI module is mounted to which the present invention can be applied. FIG. is a partially enlarged sectional view showing another preferred form of the electrical connection device of the present invention,
Figure 5 shows how to use the connecting device shown in Figure 4.
Figure 6 is a sectional view showing the connection between the LSI module and the printed circuit board.
FIG. 7 is a partially enlarged sectional view showing another preferred form of the electrical connection device of the present invention; FIG. An enlarged view showing an example of a contact pin that can be used in the connection device shown in FIG.
Figure 9 shows how to use the connection device shown in Figure 7.
FIG. 10, a sectional view showing a state in which the connection is made between the LSI module and the printed circuit board, shows another preferred electrical connection device of the present invention in which a metal coating is formed on the inner surface of the guide hole. FIG. 11, a partially enlarged cross-sectional view showing the configuration, shows another preferred electrical connection device of the present invention, in which the surface of the connection board in contact with the module is coated with a low-conductivity insulating resin material. A partially enlarged sectional view showing the morphology,
Figures 12, 13a, 13b, 13c
14a and 14b are schematic diagrams showing an example of a heating element pattern that can be used in the present invention, and FIGS. 15 and 16 are respectively diagrams showing a heat sink metal layer attached to a connection board. FIGS. 17 and 18 are partially enlarged cross-sectional views of the electrical connection device of the present invention, showing an example in which the electrical connection device is built in, and FIGS. FIG. 3 is a partially enlarged sectional view of the electrical connection device. In the figure, 1 is a connection board, 2 is a guide hole, 3 is a metal reservoir, 4 is a low melting point metal, 5 is a heating element, 8 is a metal layer for a heat sink, 10 is an electrical connection device, and 11, 12 and 31 are contacts. It's a pin.

Claims (1)

[Claims] 1. A device interposed between electrical devices to electrically connect their contact pins, comprising: a connection board made of an insulating material; a hole drilled through the connection board; , a guide hole with a constant inner diameter into which a contact pin of an electrical device can be inserted, a cylindrical metal reservoir formed approximately in the center of the guide hole, a melting point 100 mm housed in the metal reservoir and used for connection between the contacts. It is characterized by comprising a combination of a low melting point metal of ~170°C, and a heating element disposed inside the connection board and near the metal reservoir for melting the low melting point metal. Electrical connection device. 2. The electrical connection device according to claim 1, wherein the insulating material is a ceramic material. 3. The electrical connection device according to claim 1, wherein the insulating material is a dendritic material. 4. The electrical connection device according to any one of claims 1 to 3, wherein both ends of the guide hole are chamfered. 5. The electrical connection device according to any one of claims 1 to 4, wherein the inner surface of the guide hole is coated with a metal material. 6. Claims 1 to 5, wherein the surface of the connection board that contacts the module of the electrical device is coated with an insulating resin material having low thermal conductivity.
The electrical connection device according to any one of the above items. 7. The electrical connection device according to any one of claims 1 to 6, wherein the low melting point metal is an In-Sn alloy. 8. The electrical connection device according to any one of claims 1 to 7, wherein the heating element is a thick film or thin film resistor. 9 Claims 1 to 8, wherein a heat sink metal layer is formed near the metal reservoir.
The electrical connection device according to any one of the above items. 10 A device that is interposed between electrical devices to electrically connect the contact pins of one electrical device and the circuit pattern on the surface of the other electrical device, a connection board made of an insulating material, which penetrates the connection board. a guide hole with a constant inner diameter into which a contact pin of an electrical device can be inserted; A metal reservoir with a cross section that expands into a funnel shape, a low melting point metal with a melting point of 100 to 170°C, which is used for connection between contacts, housed in the metal reservoir, and a metal reservoir that is inside the connection board and is located inside the metal reservoir. An electrical connection device comprising: a heating element disposed nearby for melting the low melting point metal; 11. The electrical connection device according to claim 10, wherein the insulating material is a ceramic material. 12. The electrical connection device according to claim 10, wherein the insulating material is a resin material. 13. The electrical connection device according to any one of claims 10 to 12, wherein the inner surface of the guide hole is coated with a metal material. 14. Claims 10 to 14, wherein the surface of the connection board that contacts the module of the electrical device is coated with an insulating resin material having low thermal conductivity.
The electrical connection device according to any one of Item 13. 15. The electrical connection device according to any one of claims 10 to 14, wherein the low melting point metal is an In-Sn alloy. 16. The electrical connection device according to any one of claims 10 to 15, wherein the heating element is a thick film or thin film resistor. 17. Claims 10 to 17, wherein a heat sink metal layer is formed near the metal reservoir.
The electrical connection device according to any one of Item 16. 18 A device interposed between electrical devices to electrically connect the contact pins of one electrical device and the circuit pattern on the surface of the other electrical device, a connection board made of an insulating material, which penetrates the connection board. a guide hole with a constant inner diameter into which a contact pin of an electrical device can be inserted; a metal reservoir with a tapered cross section, a low melting point metal with a melting point of 100 to 170° C., which is used for contact connection, housed in the metal reservoir, and a metal reservoir disposed inside the connection board and in the vicinity of the metal reservoir; and a heating element for melting the low melting point metal. 19. The electrical connection device according to claim 18, wherein the insulating material is a ceramic material. 20. The electrical connection device according to claim 18, wherein the insulating material is a resin material. 21. The electrical connection device according to any one of claims 18 to 20, wherein the inner surface of the guide hole is coated with a metal material. 22. Claims 18 to 22, wherein the surface of the connection board that contacts the module of the electrical device is coated with an insulating resin material having low thermal conductivity.
The electrical connection device according to any one of Item 21. 23. The electrical connection device according to any one of claims 18 to 22, wherein the low melting point metal is an In-Sn alloy. 24. The electrical connection device according to any one of claims 18 to 23, wherein the heating element is a thick film or thin film resistor. 25 Claims 18 to 25, wherein a heat sink metal layer is formed near the metal reservoir.
The electrical connection device according to any one of paragraphs 24 to 25.