This disclosure describes an electrical connector for joining microcircuit or microcircuit modules, such as leadless integrated or hybrid circuit carriers to utilization means, such as printed or etched circuit boards or similar means. The electrical contacts through which the microcircuit and utilization means are connected are formed and etched in place on an elastomeric material, precisely located; the material acting as a restoring force to maintain connection. The connector when used in a system maintains transmission line mediums in a single environment.

Patent
   RE31114
Priority
Nov 13 1975
Filed
Nov 17 1980
Issued
Dec 28 1982
Expiry
Dec 28 1999
Assg.orig
Entity
unknown
23
11
EXPIRED
6. A high-frequency electrical connector system for electrically interconnecting a conductive path of a first circuit element with a conductive path of a second circuit element, said system comprising:
(a) a resilient member having a surface defined by two protruding portions and an intermediate indented portion;
(b) a contact of flexible metallic material overlaying a substantial part of each said portion of said surface of said resilient member and extending no further than the boundaries of said surface, said contact member also having a surface defined by two protruding portions and an intermediate indented portion, said surfaces of said resilient member and said conduct member being further configured such that said resilient member provides a restoring support for said contact member and such that a common force applied against both protruding portions of said contact member causes said portions to move away from each other;
(c) rigid frame means for holding said resilient member and said contact member against said circuit elements such that a first protruding portion of said contact member touches a conductive path of said first circuit element and a second protruding portion of said contact member touches a conductive path of said second circuit element; and
(d) means for urging said frame means, and thereby said resilient member and said contact member, further against said circuit elements so as to cause said protruding portions of said contact member to move away from each other and thereby wipingly engage said conductive paths. PAR
1. A high frequency electrical connector system for making electrical connections between a microcircuit and a circuit board comprising:
a circuit board having first electrical conductive path means fixed upon a surface thereof;
a microcircuit having second electrical conductive path means fixed upon a surface thereof;
1ocation means provided by said circuit member of for locating said microcircuit along said circuit board so that said first and second electrical conductive path means are positioned adjacent to each other; and
means for electrically connecting said first and second electrical conductive path means together, including
(a) frame means,
(b) elastomeric material removably attached to said frame means and being deformable to exert a resilient force,
(c) conductive material in the form of electrical contacts bonded to an undulating surface of said elastomeric material to electrically engage respective ones of said first and second electrical conductive path means, and
(d) securing means for removably securing said frame means to said circuit board with said electrical contacts on said elastomeric material electrically engaging said first and second electrical conductive path means, said elastomeric material being deformed by said securing means so that said resilient force causes said electrical contacts to wipingly engage said first and second electrical conductive path means thereby forming an electrical connection therebetween and maintaining said
microcircuit in position on said circuit board.
2. A high frequency electrical connector system of claim 1 wherein said circuit board has a ground plane on another surface thereof and said microcircuit has a conductive coating on another surface thereof, said conductive coating being in electrical engagement with said ground plane.
3. A high frequency electrical connector system of claim 1 wherein said first and second electrical conductive path means are in the same plane.
4. A high frequency electrical connector system of claim 1 wherein said first and second electrical conductive path means are positioned in stepped relationship to each other.
5. A high frequency electrical connector system of claim 1 wherein said location means comprises an opening in said circuit board into which said microcircuit is disposed.
7. The connector system of claim 6 wherein said frame means includes means defining a chamber, and wherein said resilient member includes a third portion configured for mating insertion into said chamber.
8. The connector system of claim 6 wherein said resilient member is elongate in form, and wherein said surface thereof defines a pair of protruding ridges separated by an elongate indentation, further comprising a plurality of said contact members spaced along said resilient member in a longitudinal direction.
9. The connector system of claim 8 wherein each said contact member extends across said resilient member in a lateral direction. 10. The connector system of claim 6 wherein a first protruding portion of said contact member is separated from a second protruding portion by a first distance in a first direction and offset from said second portion by a second distance in a second direction so as to define with said second portion a contact member of stepped configuration for interconnecting conductive paths in non-coplanar alignment.
11. The connector system of claim 6 wherein said frame means comprises a rigid frame member of rectangular configuration, and wherein said resilient member is of mating rectangular configuration, further comprising a plurality of said contact members spaced around the periphery of said resilient member so as to permit the interconnection of a like plurality of conductive paths of a first circuit element located within the enclosure of said frame member with a like plurality of conductive paths of a second circuit element located without said enclosure.
12. The connector system of claim 6 wherein a surface of said resilient member proximate at least one edge thereof defines a pair of elongate protruding ridges separated by an elongate indentation and wherein each said contact member spaced therealong extends across both said ridges.
13. The connector system of claim 6 wherein said indented and protruding portions of said surface of said contact member define an undulating surface including a concave portion interposed between two convex portions.
14. The connector system of claim 6 wherein said contact member is of longitudinal configuration having a width dimension substantially greater than its thickness dimension.

This is a continuation of application Ser. No. 631,591 filed Nov. 13, 1975, now abandoned.

In the prior art there are various types of connectors in general use. Numerous expedients exist for the connection of elements of flexible circuitry to each other or to printed circuit boards having like spacing between their conductive leads. For example, one of the more common type of connectors uses male or female components where one component is mounted on a circuit board and the other attached to a conductor. This is quite bulky, requires considerable area and transmission mediums are not maintained. Another connection scheme for overcoming the disadvantages of bulkiness and area required is to use a cable which is preferably flat and having insulation removed at one end co-planer thier their free ends to their other ends joined in common. The leg portions may have bifercated bifurcated contacts at their free ends for further engaging with the transmission mediums. Contact means 12B may include two pairs of spaced leg portions which are spaced apart and extend substantially parallel from their free ends to the other ends or the contact may be as the contact means 12C which is a single leg portion. The contact means 12A-12C are flat in the direction of double headed arrow 11. It should be emphasized that the contacts shown in FIG. 4 are the preferred, but that other shapes and designs can be used depending upon the particular application.

Referring now to FIG. 5, there is shown another embodiment of the subject invention. FIG. 5A shows the contact system similar to FIG. 3A but in FIG. 5B, which is taken along the line BB of FIG. 5A, the contact means 12 is provided in a stepped rather than flat configuration. This is because microcircuit means 18 is mounted flush with the surface of utilization means 14 which requires that the serpentine shape of the contact means 12 be stepped, since the transmission mediums 16 and 20 are now not co-planer co-planar. As the microcircuit is mounted flush with the surface of utilization means 14, a device locating means such as device locating means 17 of FIG. 2 is not required and the principal locating means becomes the alignment means 28, shown in FIG. 2. Additionally, the elastomeric material 10 in this embodiment is adapted to be carried by unit 22, thus the unit is channeled so that when secured to utilization means 14 it will capture material 10 to precisely locate the contacts. Another embodiment may, however, include no channel and the unit 22 made to forcibly hold the elastomeric material 10 in position once secured to the utilization means 14.

The above described connector or connector systems has advantages over other connector schemes in that in the mated state equal pressure is applied all along the microcircuit means which insures good electrical contact and good thermal contact. By careful design of the shape of ridges in the elastomeric material, a wiping action is made at contact or during connection. The elastomeric material acts as a restoring force and maintains pressure during the lifetime of the connector, has good compression set characteristics and is inert to acid and most all electronic chemicals except strong solvents like tolenetoluene. Since contact means 12 mate mediums 16 and 20, as described, thermal expansion of the substrate, i.e., used to carry the microcircuit means, does not break or interrupt the contact. Contact is always maintained during shock and vibration. The connector system, according to the subject invention, makes tests and integration of system of microcircuits easy as well as field replacement of a microcircuit. No soldering (bonding) to the substrate is necessary to make connection for a next higher assembly. Considering manufacturing capability, accumulation of manufacturing tolerances for combined components of the contact system are about plus and minus 0.0010-inch. Therefore, the contact system can be mass produced.

Referring next to FIG. 6, there is shown a switch in accordance with the subject invention. A support plate 42 which could be similar to utilization means 14 includes fixed transmission line elements 44 secured to the support plate and a movable switch contact 46 secured to an elastomeric material mounting means 48 on said support plate for movement between a closed position engaging said fixed contact to join or connect transmission line elements and a open position spaced from said fixed contact and actuator means 50 for moving the movable switch contact toward and away from the support plate between said open and closed positions. Actuator means 50 could be, for example, a cam switch, a slide switch, etc. Alternatives to the switch include providing a plurality of fixed switch contacts attached to support plate and a plurality of movable switch contacts secured to the elastomeric material.

Referring now to FIG. 7, there is shown a relay in accordance with the present invention. A housing member 52 includes signal input and output connectors 54, 56 respectively, such as coaxial cable connectors, and means for connecting the signal input and output connectors to say interrupted transmission line means 58 on a substrate 60. The elastomeric material 10 having contact means 12 according to the present invention is next provided. To operate as a relay, solenoid or mechanical pressure indicated by the arrow 62 causes the contact means to connect the interrupted transmission line means allowing a signal to pass through the unit. Therefore, the interrupted transmission lines can be considered as fixed relay contacts carried by the housing, the elastomeric material and contact means as movable relay contacts, and the solenoid pressure as an actuator means for moving the movable relay contact between a closed position and an open position. An alternative would be to provide additional movable relay contacts and having common actuator means.

Turning now to the process of securing the contact means to the elastomeric material, an object of the subject invention, there is shown in FIG. 8 a block diagram flow chart therefor. The first step in the process, as in any process, is the selection of a raw material. Various base metals can be used; wrought or rolled nickel, an alloy of Beryllium-Nickel, or an alloy of Copper-Beryllium which is preferred. It has been found that nickel presents slight manufacturing problems, such as bending too easily, creases, etc., whereas the alloy of Beryllium-Nickel reduces the above manufacturing difficulties but it is hard to etch, which is required by the hereinafter described process. The Copper-Beryllium alloy, however, allows most of the manufacturing and process difficulties to be overcome. The thickness of the wrought or rolled alloy is important to the process; too thick invites undercutting which eventually leads to the possibility of short circuits, too thin invites manufacturing handling problems. A thickness of 0.0015 to 0.0025, preferably 0.002-mils thick, has been utilized. (Undercutting is well known in circuit board and photo processing techniques.)

The second step of the process includes a blanking and punching of the raw material. Blanking enables the wrought or rolled alloy to be handled easily by simply cutting the material to a size necessary for the process. Punching simply punches tooling holes into the material so that further processing and alignment is possible.

The third step of the process uses conventional photographic techniques to provide the contact means. The process is fully explained on pages 1-5 through 1-17, specifically FIG. 7b on page 1-11, in Handbook of Electronic Packaging, edited by Charles A. Harper, Copyright 1969 by McGraw-Hill, Inc. The desired shape, number and spacing of the contact means (three are shown in FIG. 4 as 12A, 12B and 12C) are provided in the form of a contact pattern, or mask, and precisely aligned using the punched holes. A negative mask is preferred, but can be a positive. Once the desired contact areas have been photographically defined in the photo resist, the actual contact means are provided by plating a layer of nickel, followed quickly by a plating layer of gold, each having a thickness of 5 to 6 microns. As is well known, the two platings must be preformed in a very short time to prevent oxidation of the metals. Additionally, if nickel is used as the raw material, onto which the desired contacts are formed, only gold need be plated. Further, gold contacts are preferred because gold is usually the transmission mediums previously discussed. Thus, gold transmission lines on the utilization means, gold contacts, and gold transmission mediums on the microcircuit (gold-gold-gold) provides a very compatible connection scheme. The photo resist is then removed.

Step four of the process is to heat and cool the photographically processed unit for softening and making the metal contacts less brittle, i.e., annealing. A flat contact, say, for use in a connection system similar to that shown in FIG. 3 where the transmission mediums are substantially co-planer co-planar need not be necessarily subjected to annealing, but it is preferred. Where the connection system is used, similar to that shown in FIG. 5, i.e., a stepped configuration, the annealing process is required and even more so when the contacts are nickel under gold as in the preferred embodiment. The annealing temperature should be between 400° and 600°C, preferably 500°C, for one hour. Step 4 also includes preforming the annealed unit to the desired shape, i.e., step. The preforming is similar to conventional methods whereby the annealed unit is merely placed over a die and pressure applied via some means to form the annealed unit into the shape of the die.

The annealed and preformed unit, or annealed unit, as the case may be, is then subjected to a cleaning, partial etch and application of a primer on the raw material opposite the side to which the metal contacts have been deposited. The partial etch affects the monolayers of the material to insure a clean surface onto which the elastomeric material will be applied. Having the surface cleaned and primed, the unit is placed into a die installed in a conventional transfer molding machine. The elastomeric material is then injected in the areas desired. In the case of the subject invention, the elastomeric material is injected along the contacts but on the opposite side. The unit then undergoes a partial cure in the transfer molding machine. After the partial cure, the entire unit is subjected to a postbaking process to obtain a final cure and to outgas any curing agents, catalyst by-products, etc. and to obtain the optimum characteristics of the elastomeric material.

The final step of the process is to remove the raw material which is exposed, i.e., not covered by gold. This is accomplished by a spray etch and enables all exposed raw metal material to be removed without affecting the contact or elastomeric material. The unit is, of course, trimmed after etching to conform to the drawing.

Thus, there has been described a process for securing metal contacts to an elastomeric material, another object of the subject invention.

While there has been shown and described the preferred embodiments according to the subject invention, it will be apparent to those skilled in the art that many changes and modifications may be made without departing from the invention in its broader aspects. For example, two connection systems could be disposed on opposite sides of the utilization means and mounted thereto by common securing means, or a series of connection systems could be utilized. Therefore, the appended claims are intended to cover all such changes and modifications that fall within the true spirit and scope of the invention.

Berg, William E.

Patent Priority Assignee Title
4508399, Jan 03 1984 AMP Incorporated Polarized ribbon cable connector having circuit components therein
4683425, Oct 30 1984 AMPHENOL CORPORATION, A CORP OF DE Integrated circuit test clip
4744764, May 27 1986 Rogers Corporation Connector arrangement
4768971, Jul 02 1987 Rogers Corporation Connector arrangement
4830623, Feb 10 1988 Rogers Corporation Connector arrangement for electrically interconnecting first and second arrays of pad-type contacts
4899099, May 19 1988 Augat Inc Flex dot wafer probe
4910415, Dec 15 1982 Sharp, Kabushiki Kaisha Interconnection between a battery cell and a printed circuit board in an electric apparatus
4980635, Dec 26 1984 Hughes Aircraft Company Integrated circuit package carrier
5071359, Apr 27 1990 Circuit Components, Incorporated Array connector
5113580, Nov 19 1990 RANDALL J HARTGROVE,; JON M SCHROEDER,; JOSEPH F LONG, Automated chip to board process
5216583, Jul 18 1990 KEL Corporation Device for mounting a flat package on a circuit board
5227959, May 19 1986 HEWLETT-PACKARD DEVELOPMENT COMPANY, L P Electrical circuit interconnection
5245751, Apr 27 1990 Circuit Components, Incorporated Array connector
5435733, Nov 12 1993 YAKISAMI CAPITAL CO L L C Connector assembly for microelectronic multi-chip-module
5530291, Mar 25 1994 International Business Machines Corporation Electronic package assembly and connector for use therewith
5754401, Feb 16 1996 Sun Microsystems, Inc. Pressure compliantly protected heatsink for an electronic device
6320756, Jan 18 1999 ALPS Electric Co., Ltd. Electronic device mounting structure using electronic device mounting member and cushioning
6646565, Jun 01 2000 Hypercom Corporation Point of sale (POS) terminal security system
6823582, Aug 02 2002 National Semiconductor Corporation Apparatus and method for force mounting semiconductor packages to printed circuit boards
6917299, Jun 01 2000 Hypercom Corporation Point of sale (POS) terminal security system
7171745, Aug 02 2002 National Semiconductor Corporation Apparatus and method for force mounting semiconductor packages to printed circuit boards
7476107, Sep 01 2006 Hon Hai Precision Ind. Co., Ltd. Socket connector with retaining device
RE34190, May 17 1990 ADFLEX SOLUTIONS, INC Connector arrangement
Patent Priority Assignee Title
3054879,
3199067,
3335327,
3597660,
3600528,
3670205,
3717737,
3874768,
3904262,
3987259, Jun 12 1975 Globe-Union Inc. Membrane switch apparatus having sequential bridging contact arrangement
4072816, Dec 13 1976 International Business Machines Corporation Integrated circuit package
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Executed onAssignorAssigneeConveyanceFrameReelDoc
Nov 17 1980Tektronix, Inc.(assignment on the face of the patent)
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