JPS63141274A - Connector device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to high-density board mounting technology, and in particular, to securely mounting a large number of electrodes formed at high density on a large-area board used in large-scale computers, etc. The present invention relates to a connector device suitable for connecting to.

[Conventional technology]

In order to improve the speed and performance of large computers, it is desired to have a large number of terminals. In response to this request, Japanese Patent Application Laid-Open No. 60-253
As described in No. 177, fine pins are planted in the input/output terminals on the wiring board on which the integrated circuit chip is mounted, and the inside of the receptacle plate provided on the main board on which the wiring board is mounted is filled with a low melting point metal. A connector has been proposed in which electrical connection between boards is established by inserting pins into a low melting point metal that is liquefied by heating.

However, when applying this type of connector to a large board, it is extremely difficult to reliably insert and remove a large number of pins due to reduced accuracy in board sagging, pin attachment, and reduced board positioning accuracy. becomes difficult.

Further, the processing of the pins used here requires high precision, and furthermore, it is necessary to precisely implant a large number of pins into the input/output terminals of the wiring board. However, the high-precision manufacturing process increases costs, which is a problem in practical application.

[Problem that the invention seeks to solve]

In the above-mentioned conventional technology, it is necessary to insert a large number of pins arranged at a fine pitch into a cavity formed in a receptacle plate with high accuracy, and this becomes more difficult to achieve as a larger substrate is used. Furthermore, the precision required for the pin forming process is severe, making it difficult to put the above-mentioned conventional technology into practical use.

The purpose of the present invention is to solve the above-mentioned problems, to absorb positional deviations between connection terminals due to board warping, positional deviation, etc., and to provide accuracy including processes for processing pins and planting pins on boards. The objective is to eliminate the need for a high pin formation process.

[Means for solving problems]

In the present invention, in order to achieve such an object, a cavity is formed or a septacle is mounted on the above-mentioned wiring board, the cavity is filled with a low melting point metal, and a cavity is formed in the flexible substrate fixed to the main board. forming a connection signal terminal on the inner wall of the cavity, filling the cavity with a low melting point metal and a connection pin;

After alignment with the cavity of the receptacle plate fixed to the wiring board, both cavities are penetrated with a connecting pin in a state where the low melting point metal is melted to obtain an air-like connection between the boards. Thereby, positional deviation between the connection terminals can be absorbed, and a highly accurate pin formation process can be made unnecessary.

[Effect]

In the present invention, a cylindrical shape such as a general wire-drawn material is sufficient for the connecting pin, and no special knife is required. Further, the connecting pin only needs to be in contact with two low-melting point metals, and does not need to have an exact length. In the conventional technology, it was necessary to increase the bottom area of the pin to increase the connection reliability between the board and the pin, and to make the tip of the pin thinner to increase the mating margin. That is, the present invention simplifies the pin manufacturing process. In addition, in the conventional technology, pins must be planted perpendicularly to the board surface, and the uprightness directly affects the mating margin of the connector, but in the present invention, such highly precise pin planting is possible in a process. do not need.

Therefore, according to the present invention, the pin forming process is simplified, and the manufacturing cost of the connector can be reduced.

In addition, the spacing between the flexible board and the wiring board can be freely adjusted within the range where the connecting pins and low-melting point metals are in contact, so even if one board is warped, it will be completely protected against displacement in the direction perpendicular to the board surface. can be followed. In the conventional technology, in order to absorb displacement in the vertical direction to the board surface, it was necessary to divide the connector into multiple parts and have each connector absorb the displacement independently, but with the present invention, the connector can be precisely adjusted in the vertical direction. Positioning becomes unnecessary, and the number of connector divisions can be reduced.

Another advantage arises by using a material with a higher melting point as the low melting point metal filled in the cavity formed in the flexible substrate than the low melting point metal filled in the receptacle on the wiring board. At temperatures where only the low melting point metal in the receptacle on the wiring board melts,
The low melting point metal in the flexible substrate does not melt, and the connector can be pulled out while maintaining the connection between the connection pin and the flexible substrate. Since the connecting pins maintain positional deviations between the connecting terminals due to board warping, etc., when connecting the same connector and wiring board again, the pins can be inserted extremely accurately.

That is, once insertion is completed, the positions of the connecting pin and the connecting terminal are automatically optimized, the positional relationship can be maintained, and subsequent insertion and removal can be performed reliably.

〔Example〕

Hereinafter, five aspects of the present invention will be explained in detail with reference to the drawings. FIG. 1 is a sectional view of a connector device according to a first embodiment of the present invention, and FIG. 2 is a perspective view of a main body of a computer using the connector device according to this embodiment.

As shown in FIG. 2, a module board 2 mounted with a large number of integrated circuit chips 1 and hermetically sealed is stack-mounted with two main boards 3, and each module board 2 is connected to a main board 3 and a flexible board. It is electrically connected through 4. As shown in FIG. 1, input/output terminals 5 are formed on one end of the module board 2, and Si IJ septacles 6, each having cavities formed at intervals equal to the terminal pitch, are fixed with an adhesive 7. There is. Each cavity contains 8 low melting point metals.
is filled. These Si receptacle processing methods and low melting point metal filling methods are described in detail in JP-A-60-253177.

On the other hand, the connection terminals 9 on the main board 3 and the connection terminals 10 on the flexible board 4 are connected by solder balls 11, and resin 12 is filled between the boards to maintain connection strength.

FIGS. 3(a) to 3(d) are cross-sectional views showing the process of forming the flexible substrate 4. FIG. As shown in FIG. 3(a), a polyimide film 13 that has excellent flexibility and can withstand high temperatures such as solder reflow is used as a base, and a copper foil 15 as a wiring material is bonded using an adhesive 14. Next, as shown in FIG. 3(b), a wiring pattern 16 is formed by etching.

The copper-polyimide sheets formed as described above are laminated at once through a polyimide film 18 coated with an adhesive 17, as shown in FIG. 3(C), to form a multilayer flexible substrate. In large-scale computers, which is one of the fields of application of the present invention, since high-speed pulse signals are transmitted, the characteristic impedance of wiring has a large effect on signal delay and distortion. In such a case, it is desirable to use a wiring structure with well-known impedance, for example a stripline structure as shown in FIG. 3(d). In FIG. 3(d), 19 is a signal layer and 20 is a ground layer 4. FIG. 4 shows the structure of the connecting terminal 10 in FIG. 1 and one end of the flexible substrate 4 on which the connecting terminal 10 is formed. There is. Since the polyimide film 13 has flexibility, the copper foils 15 of each wiring layer are stacked in a shifted manner so that the copper foils 15 are exposed, and the connection terminals 10 are formed at one end of the copper foils 15 of each wiring layer.

Next, as a main part of the present invention, a connection structure between the flexible substrate 4 and the module substrate 2 shown in FIG. 1 will be explained. 5(a) and 5(b) are cross-sectional views showing the process of forming one end of the flexible substrate 4 to be connected to the module substrate 2. FIG. As shown in FIG. 5(a), through holes are formed by cutting with a drill or the like in the flexible substrates 4 laminated together, and connection terminals 21 are formed on the side surfaces of the through holes by Cu plating. Next, on the bottom surface of the flexible board 4,
The hollow Si receptacle 22 is fixed using an adhesive 23. Next, as shown in FIG. 5(b), the through holes are filled with solder 24, and the solder 24 is heated.
The connecting pins 25 are inserted all at once using a jig without melting.

FIG. 6 shows an example of the structure of a jig for inserting the connecting pin 25 into the cavity of the flexible substrate 4 in FIG.

The wire drawing material 28 wound around the drum 27 in the pin material supply device 26 is supplied into the cavity of the flexible substrate 4 through the guide hole of the insertion jig 29. When inserting, align the flexible board 4 and the jig 29, and reduce the force Ω.
The low melting point metal 24 in the flexible substrate 4 is melted by heat, and the wire-drawn material 28 is inserted by a certain length.

The cutter 30 cuts the material into multiple pieces.

After the assembly of the flexible substrate 4 and the attachment of the flexible substrate 4 to the module substrate 2 are completed by the process described above in FIGS. 3 to 6, the Si on the module substrate 2 is After aligning the receptacle 6 and the flexible substrate 4, the low melting point metals 8 and 24 are melted by heating, and the connecting pins 25 are inserted.

In the conventional technology, the processing accuracy of this connection pin is important. FIG. 7(a) is an example of the cross-sectional shape of a connecting pin used in a conventional example, with a pedestal diameter a=0.21OI,
Pedestal height b = 0.1 inch, pin length c = 0.3 inch,
Machining of pin diameter d = 0.06 m is required.

Processing methods include grinding, electrical discharge machining, etching,
Examples include electroforming, casting, wire bonding processes, etc., but all of them inevitably increase costs in order to improve processing accuracy. On the other hand, in the present invention.

A cylindrical pin as shown in FIG. 7(b) is used. As for the size of the connection pin, for example, the diameter a'=o, 1cm, and the length b'==1ms+ can be considered. However, as is clear from the fitting mechanism of the connecting pin 25 shown in FIG. 1, it is not necessary to strictly limit the accuracy of the length b' as long as the condition is that electrical continuity is satisfied. That is, if the length is longer than the distance between the opposing surfaces of the low melting point metal 8 and the low melting point metal 25, connection is possible in principle, and some variation in b' is allowed.

FIG. 8 is a cross-sectional view showing the connection state of the flexible substrate 4 in the first embodiment of the present invention when the vertical axis of the module substrate 2 is so large that it cannot be ignored. If the warpage of the module board 2 is not negligible compared to the entire board, what is most affected is the displacement of the connection terminal 5 in the direction perpendicular to the board surface. However, according to the present invention, if the low melting point metals 8 and 24 are in a molten state, the connecting pins 25 can be opened in the vertical direction on the module board 2 surface. When the vertical axis is about 1 mm, the displacement X in the vertical direction is about 100 μm in a connector with length y=20. In the conventional technology, the contact length between the pin and the low-melting point metal differs by the displacement X between the central part and the peripheral part of the connector, and the cancerous alloy phase decreases.

Therefore, it was necessary to further divide the connector and allow each connector to absorb the warping of the board. That is, according to the present invention, the number of divisions of the υ connector can be reduced.

FIGS. 9(a) and 9(b) are cross-sectional views showing a second embodiment of the present invention. Here, a material having a higher melting point than the low melting point metal 8 is used as the low melting point metal 24. When pulling out the flexible substrate 4, the temperature is maintained at which only the low melting point metal 8 melts. As shown in FIG. 9(b), the connecting pins 25 are fixed to the low-melting point metal 24, so that misalignment between the connecting terminals due to warping of the board or the like can be maintained. Then, when connecting the flexible substrate 4 again, the temperature is maintained at such a temperature that only the low melting point metal 8 melts. If the substrates are the same, the positional deviation of the connection terminals is maintained, so that the low melting point metal 8 such as the connection pin 25 is reliably connected, and a stable connection can be maintained even during subsequent insertion and removal.

〔Effect of the invention〕

As described above, according to the present invention, the positional deviation between the connecting terminals can be adjusted without requiring a high-precision connecting pin forming process, and
Since a stable connection can be maintained thereafter, it is effective for connection technology between high-density wiring boards.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a first embodiment of the invention. FIG. 2 is a perspective view of the computer main body using the first embodiment of the present invention. FIGS. 3(a) to (d) and FIG. 4,
FIGS. 5(a) to Φ) are cross-sectional views illustrating an example of intermediate steps in manufacturing the first embodiment of the present invention. FIG. 6 is a diagram illustrating an example of a pin insertion jig including an embodiment of the present invention. FIG. 7 is a sectional view showing an example of the shape of the connecting pin of the conventional example and the embodiment of the present invention. FIG. 8 is a sectional view showing a first embodiment of the present invention. FIG. 9 is a sectional view showing a second embodiment of the present invention. 1...Integrated circuit chip%2...Module board, 3
... Main board, 4... Flexible board, 5... Input/output terminal, 6... S i IJ receptacle, 7...
Adhesive, 8... Low melting point metal, 9... Input/output terminal on main board, 10... Input/output terminal on flexible board, 11
...Solder ball, 12...Resin, 13...Polyimide film, 14...Adhesive. 15...Copper foil, 16...Wiring pattern, 17...
Adhesive, 18... Polyimide film, 19... Signal layer, 20... Ground layer, 21... Connection terminal, 22...
...8 i receptacle, 23...adhesive, 24.
...Low melting point metal, 25...Connection pin, 26...Pin material supply device, 27...Drum. 28... wire drawing material, 29... jig, 30...
Cutter〇Representative Patent Attorney Katsuo Ogawa〆・'π\,2S...Se【
E-pin 4. ,． 71~shi1ruhedama (tail...arrangement collection hafun 25...bond enterhihihi nth 60.6 (α small (b) the δth

Claims (1)

[Claims] 1. The first connection terminal of the first substrate and the second connection terminal of the second substrate
A connector device for connecting a connecting pin fixed to a connecting terminal of a second substrate with a low melting point metal in a first cavity of a receptacle plate fixed to a first substrate.
forming a cavity, providing the second connection terminal on the inner wall of the second cavity, filling the second cavity with a low melting point metal, and penetrating the first cavity and the second cavity with the connection pin. A connector device characterized in that the connecting pin and the second connecting terminal are connected by a low melting point metal in the second cavity. 2. The connector according to claim 1, wherein the melting point of the low melting point metal filled in the second cavity is higher than the melting point of the low melting point metal filled in the first cavity. Device.