JPH08293340A - Elastomer connector - Google Patents

Abstract

PURPOSE: To provide an elastomer connector with which modules comprising a plurality of lands arranged at narrow pitches in a flat shape, substrates, etc., are properly and mutually connected with low height. CONSTITUTION: This elastomer connector 1 is constituted of an FPC 2, in which a plurality of conductive patterns 4 provided with pairs of band-like beams 5, 5 having a slit between them are formed and rod-like elastic bodies 3. The band-like beams 5, 5 are formed in a manner such that the beams are projected in reverse directions relative to the flat face of the polyimide layer 7 of the FPC 2. The elastic bodies 3 are installed in the spaces between the band-like beams 5, 5. Consequently, the conductor patterns 4 of the FPC 2 are used as contacts of the elastomer connector 1, so that the height is further lowered and the pitches are further narrowed, and at the same time production of the connector is facilitated.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrical connector, particularly a multi-chip module having a plurality of flat lands, a land grid array or a substrate (hereinafter referred to as a module), and an interconnection between the substrate. Regarding the elastomer connector.

[0002]

2. Description of the Related Art As a conventional connector for connecting a module having flat lands to a substrate, a contact formed by processing a metal material into a shape capable of applying a contact pressure perpendicular to an opposing land, and A so-called interposer connector composed of an insulating housing for fixing these contacts is known (Japanese Patent Laid-Open No. 63-43279).
No. On the other hand, a so-called elastomer connector having a structure in which a flexible printed circuit board (hereinafter referred to as FPC) on which a conductor pattern is formed as a contact is wound around an elastic body is also known (US Pat. No. 3,985,413). ).

[0003]

In the former connector, each contact is inserted into an insulating housing having a cavity formed in an area array, and the contact is prevented from jumping out of the cavity, for example, in the vicinity of the cavity. It is necessary to squeeze and crush the boss protrusions of. Therefore, there is a problem that not only the manufacturing is complicated and the cost is high, but also the height reduction is limited when the area array is formed due to the limitation of the metal spring characteristics. For example, 1.
A height of less than 2mm on a 27mm grid is very difficult.

Further, in the latter connector, cracks may occur on the surface of the conductor pattern due to the reduction of the bending radius of the FPC, so it is difficult to reduce the height to 0.8 mm or less. In addition, there is the possibility of short-circuiting with adjacent contacts. Further, when the area array is formed as shown in FIG. 9, it is difficult to thin the partition wall 91 of the insulating housing 90 due to the difficulty of molding, so the pitch between the contact rows is set to 1.67 mm or less. Difficult to do. Therefore, an object of the present invention is to provide a connector that solves the above-mentioned problems, that is, an elastomer connector having a low profile, high density, and low cost.

[0005]

The elastomer connector of the present invention is a connector for interconnecting two connected members each having a flat surface in a state of being opposed to each other, and a plurality of pairs of conductors adjacent to each other via slits. The strips are arranged so as to bridge a plurality of insulating strips arranged in parallel and spaced apart from each other, and the conductor strips of each pair project in opposite directions with respect to the plane of the insulating strip. Characterized in that a rod-shaped elastic body is arranged in the space between each pair of conductor strips.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT A preferred embodiment of the elastomer connector of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a perspective view showing an embodiment of the elastomer connector of the present invention. FIG. 2 is a cross-sectional view showing a state in which a board and a module or the like are interconnected using the connector of FIG. FIG. 3 is a perspective view showing a manufacturing process of the connector of FIG. 1, and is an (A) FPC manufacturing process, (B) forming process, and (C) elastic body inserting process, respectively.

The connector 1 is a polyimide layer (insulating band).
Flexible printed circuit board (FP
C) 2 and an elastic body 3 such as silicone.
A plurality of conductor patterns 4 made of copper foil are electrically and independently formed on the FPC 2. The shape of one conductor pattern 4 is a pair of strip-shaped beams (conductor strip portions) 5 extending substantially in parallel.
5 is made of a continuous metal foil in a square shape, and a slit 6 is formed between a pair of strip beams. Conductor pattern 4
Is functionally divided into a contact portion 10 and an FPC joint portion 11. Since the contact portion 10 is a portion for electrically connecting to the mating land, it projects in the opposing direction.

The FPC joint 11 serves to hold each conductor pattern 4 in a predetermined position, and is mechanically joined to the polyimide layer 7 of the FPC 2 at the end of the conductor pattern 4. Since the copper foil of the contact portion 10 is required to have flexibility and durability when connected to the connected body such as the substrate 31 and the module 32, a rolled foil having a thickness of 18 to 35 μm is desirable. Further, since the polyimide layer 7 is required to have rigidity for holding the conductive pattern, the thickness is preferably 25 to 50 μm. The pair of strip-shaped beams 5 and 5 forming the conductive pattern 4 are
The FPC 2 has a shape protruding in two directions orthogonal to the plane of the FPC 2, and the elastic body 3 is sandwiched in the space 8 between the pair. The elastic body 3 has a rod shape, and the cross-sectional shape thereof may be an elliptical shape, a rectangular shape, an inner recessed eyeglass shape, or the like other than the illustrated circular shape. The elastic body 3 is arranged such that its longitudinal direction is substantially orthogonal to the longitudinal direction of the slit 6 of the conductor pattern 4. When arranging the conductor patterns 4 in one row, 2
Forming a plurality of conductor patterns 4 between two polyimide layers 7,
One elastic body 3 is formed by being inserted into each slit 6 between each pair of strip beams 5 and 5. When the conductor patterns 4 are arranged in a lattice pattern, as shown in FIGS. 1 and 3, the conductor pattern group consisting of one row is formed in multiple stages in parallel with the longitudinal direction of the elastic body 3.

The structure and manufacturing method of the FPC 2 are as follows. The FPC 2 shown in FIG. 3A is composed of a polyimide layer 20 and a copper foil 21 formed on one surface thereof. As an embodiment of FPC which is a combination of a polyimide layer and a copper foil, there are a three-layer type in which both are bonded via an adhesive and a two-layer type without an adhesive.

The manufacturing process of a three-layer type FPC is as follows.
A gap 22 is formed on the polyimide layer 20 coated with the adhesive agent by a die, excimer laser or alkali etching.
To form. Since the processing cost of the excimer laser is high, it is cost effective to use a mold. Next, after the polyimide layer 20 in which the gap 22 is formed and the copper foil 21 are bonded together via an adhesive (not shown), the copper foil 21 is patterned by photolithography. Furthermore,
Ni plating and Au plating are applied on the patterned copper foil 21. When performing electrolytic plating, a tie bar 23 is formed as shown in FIG. 4, and a current is passed through the tie bar 23 to perform the plating on the exposed copper foil 21. After that, holes 24 are formed in the conductor pattern connecting portion of the tie bar 23 by punching or drilling in order to electrically separate the conductor patterns 4. If the gold resist method is used, the electrically independent conductor pattern 4 can be formed without forming the tie bar 23 and the hole 24.

The manufacturing process of a two-layer type FPC is as follows.
A gap 22 is formed by alkali etching on the polyimide layer 20 side of a two-layer structure FPC in which the polyimide 20 is coated and cured on the entire surface of the copper foil 21. Next, the gap 22
Resist coating from the polyimide layer 20 side,
The copper foil 21 is patterned by photolithography. Then, the resist of the polyimide layer 20 is removed,
Plating is performed in the same manner as the three-layer type. If the Ni and Au platings are electroless, it is not necessary to provide the tie bar 23 and the hole 24. Therefore, it is possible to selectively plate the electrically independent conductor pattern 4 in which the copper foil is exposed.

By any one of the above steps, F of FIG.
After the PC 2 is formed, as shown in FIG. 3B, the pair of strip-shaped beams 5 and 5 of each conductor pattern 4 are projected in opposite directions. In this step, the conductor pattern 4 may be formed using a mold, but the isolated polyimide layer 2 may be formed.
It is desirable to reduce the distance between 0 in the same direction as the longitudinal direction of the slit 6 of the conductor pattern 4 to form the above-mentioned protruding shape. In this case, it is preferable to simultaneously push the strip-shaped beams 5 and 5 from the back surface of the contact portion 10 in opposite directions so that the pair of strip-shaped beams 5 and 5 are alternately convex in the initial state.

After the shape shown in FIG. 3 (B) is secured, the distance between the polyimide layers 20 is maintained, and the distance shown in FIG. 3 (C) is maintained.
As shown in FIG. 5, the rod-shaped elastic body 3 is inserted into the space 8 between the pair of strip-shaped beams 5 and 5 of each conductor pattern 4. When manufacturing the connector 1 in which the conductor patterns 4 are arranged in a grid pattern, the elastic body 3 is arranged so as to be parallel to each conductor pattern row.

Next, a method of mounting the connector 1 will be described. When the connector 1 is used for a board or a module having a grid-shaped land, the contact portion 10 is protected by using a protective sheet 40 having an adhesive layer 41 on one surface as shown in FIG. 5 as a packaging form before connection. The pitch between the conductor patterns 4 is maintained. Next, positioning is performed with respect to the substrate 31 (FIG. 2) on one side,
The positional relationship between the connector 1 and the substrate 31 on one side is fixed with an adhesive sheet or an adhesive (neither is shown). After that, the protective sheet 40 is peeled off, the module 32 is positioned, the connector 1 is sandwiched between the substrate 31 and the module 32, and the elastic body 3 of the connector 1 is compressed and deformed by a certain amount and held, whereby the upper and lower lands 33 are formed. , 34 are electrically connected to each other.

The preferred embodiment of the elastomer connector of the present invention has been described above, but the present invention is not limited to the above-mentioned embodiment, and various modifications and changes can be made as necessary. For example, the one-sided copper foil shown in FIGS. 1 to 3,
Instead of FPC2 composed of one side polyimide layer,
It is also possible to use the double-sided polyimide layer shown in FIGS. 6 and 7, the internal copper foil type FPCs 50 and 60, or the double-sided copper foil shown in FIG. 8 and the internal polyimide layer type FPC 70.

The method of manufacturing the FPC 50 is as follows. First, the polyimide layer 51 and the single-sided polyimide layer 52
And a sub-FPC 55 having a copper foil layer 53
The sub-FPC 55 shown in FIG. 6C of C50 is manufactured, but the manufacturing method is different between the three-layer type having an adhesive and the two-layer type having no adhesive.

In the case of the three-layer type, the polyimide layer 52 is formed by a die, laser or alkali etching as shown in FIG.
An opening 56 as shown in (D) is formed, and it is attached to a solid copper foil on the entire surface with an adhesive (not shown). Next, a resist is coated on the copper foil surface and the sub-FPC 55 shown in FIG. 6C is formed by photolithography.
Is prepared.

In the case of the two-layer type, as shown in FIG. 6 (E), the copper foil layer 5 is formed on the solid polyimide layer 52 'on the entire surface.
After forming 3'by photolithography, a polyimide layer 52 'is formed by a die, laser or alkali etching.
An opening is formed in the sub-FPC 55 shown in FIG. 6C.

The two-layer or three-layer sub-FPC 55 produced by the above steps has the copper foil surface 53 formed with a die, laser or alkali etching to form an opening 57, and the polyimide shown in FIG. 6B is shown. It is adhered to the layer 51 with an adhesive. As a result, the FPC 50 shown in FIG. 6A is obtained.

The FPCs 50 and 70 shown in FIGS.
Since the polyimide layers 51, 52, and 72 are present on the back surfaces of the contact portions of the belt-shaped beams 53 and 73, the durability of the contact portions against repeated connection is improved and the damage caused by the contact of other objects with the contact portions is reduced. It In addition, F
The PC 70 has copper foils 73, 7 on both sides formed by through holes 71.
Electrical connection between 4 (however, only 73 is shown) is required. In this case, the contact portion is required to have flexibility like the FPC 2, but the copper foils 73 and 74 have a thickness of 18 μ due to the structure in which the copper foils 73 and 74 and the polyimide layer 72 are integrated.
The thickness of the polyimide layer 72 is 25 μm.
It is desirable that

In the FPC 60 shown in FIG. 7, the copper foil 62 is sandwiched between the polyimide layers or other insulating resin sheets only from the both sides of the insulating portion 61, so that the insulating portion 61 can be controlled to a desired thickness. Is. Therefore, by using the insulating portion 61 as a butting spacer, the height at the time of connection can be set to a desired height.

[0022]

According to the elastomer connector of the present invention,
Since the contact is formed by making the conductor pattern of the flexible substrate three-dimensional, it is possible to further reduce the height. Further, as compared with the conventional connector in which the metal contacts are fixed to the housing, the contacts are collectively formed by photolithography, so that the connector can be manufactured easily and at low cost. Furthermore, since the grid-shaped contacts are formed from one flexible substrate, 1.27 mm
A high-density connector below the grid can be easily obtained.

[Brief description of drawings]

FIG. 1 is a perspective view showing an embodiment of an elastomer connector of the present invention.

FIG. 2 is a cross-sectional view showing a state in which a board and a module are interconnected using the connector of FIG.

FIG. 3 is a perspective view showing a manufacturing method of the connector of FIG. 1, showing (A) FPC manufacturing step, (B) forming step, and (C) elastic body inserting step, respectively.

FIG. 4 is a front view showing a patterning state when electrolytically plating a conductor pattern.

5 is a front view showing a packaging state of the connector of FIG. 1. FIG.

FIG. 6 shows an FPC used in another embodiment of the elastomer connector of the present invention, respectively (A) perspective view and (B).
Plan view of polyimide layer, (C) Plan view of sub-FPC,
(D) Another plan view of another polyimide layer, (E) Another sub-FP
It is a top view of C.

FIG. 7 is a perspective view showing an FPC used in still another embodiment of the elastomer connector of the present invention.

FIG. 8 is a perspective view showing an FPC used in still another embodiment of the elastomer connector of the present invention.

FIG. 9 is a perspective view showing a state where the conventional elastomer connector is formed into an area array.

[Explanation of symbols]

 1 connector 2, 50, 60, 70 FPC 3 elastic body 4 conductor pattern 5, 53, 62, 73 strip beam (conductor strip portion) 6 slit 20, 51, 52, 72 polyimide layer (insulating strip portion) 31 substrate (covered) Connection object) 32 modules (connection object)

Claims (1)

[Claims] 1. A connector for interconnecting two connected objects, each having a flat surface, in a state of being opposed to each other, wherein a plurality of pairs of conductor strips, which are adjacent to each other via slits, are arranged in parallel and separated from each other. Are arranged so as to bridge between a plurality of insulating strips, the conductor strips of each pair are formed so as to be convex in mutually opposite directions with respect to the plane of the insulating strips, each pair of An elastomer connector in which a rod-shaped elastic body is arranged in the space between the conductor strips of the.