US3702500A - Method for obtaining electrical connections, especially for microcircuits - Google Patents

Method for obtaining electrical connections, especially for microcircuits Download PDF

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Publication number
US3702500A
US3702500A US59397A US3702500DA US3702500A US 3702500 A US3702500 A US 3702500A US 59397 A US59397 A US 59397A US 3702500D A US3702500D A US 3702500DA US 3702500 A US3702500 A US 3702500A
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US
United States
Prior art keywords
mercury
amalgam
members
microcircuits
conductors
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US59397A
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English (en)
Inventor
Guy G Gorinas
Jean C A Regal
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Alcatel Lucent SAS
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Alcatel SA
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Alcatel SA filed Critical Alcatel SA
Application granted granted Critical
Publication of US3702500A publication Critical patent/US3702500A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B23MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
    • B23KSOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
    • B23K35/00Rods, electrodes, materials, or media, for use in soldering, welding, or cutting
    • B23K35/22Rods, electrodes, materials, or media, for use in soldering, welding, or cutting characterised by the composition or nature of the material
    • B23K35/24Selection of soldering or welding materials proper
    • B23K35/26Selection of soldering or welding materials proper with the principal constituent melting at less than 400 degrees C
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L24/00Arrangements for connecting or disconnecting semiconductor or solid-state bodies; Methods or apparatus related thereto
    • H01L24/80Methods for connecting semiconductor or other solid state bodies using means for bonding being attached to, or being formed on, the surface to be connected
    • H01L24/81Methods for connecting semiconductor or other solid state bodies using means for bonding being attached to, or being formed on, the surface to be connected using a bump connector
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01RELECTRICALLY-CONDUCTIVE CONNECTIONS; STRUCTURAL ASSOCIATIONS OF A PLURALITY OF MUTUALLY-INSULATED ELECTRICAL CONNECTING ELEMENTS; COUPLING DEVICES; CURRENT COLLECTORS
    • H01R12/00Structural associations of a plurality of mutually-insulated electrical connecting elements, specially adapted for printed circuits, e.g. printed circuit boards [PCB], flat or ribbon cables, or like generally planar structures, e.g. terminal strips, terminal blocks; Coupling devices specially adapted for printed circuits, flat or ribbon cables, or like generally planar structures; Terminals specially adapted for contact with, or insertion into, printed circuits, flat or ribbon cables, or like generally planar structures
    • H01R12/70Coupling devices
    • H01R12/71Coupling devices for rigid printing circuits or like structures
    • H01R12/712Coupling devices for rigid printing circuits or like structures co-operating with the surface of the printed circuit or with a coupling device exclusively provided on the surface of the printed circuit
    • H01R12/714Coupling devices for rigid printing circuits or like structures co-operating with the surface of the printed circuit or with a coupling device exclusively provided on the surface of the printed circuit with contacts abutting directly the printed circuit; Button contacts therefore provided on the printed circuit
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01RELECTRICALLY-CONDUCTIVE CONNECTIONS; STRUCTURAL ASSOCIATIONS OF A PLURALITY OF MUTUALLY-INSULATED ELECTRICAL CONNECTING ELEMENTS; COUPLING DEVICES; CURRENT COLLECTORS
    • H01R4/00Electrically-conductive connections between two or more conductive members in direct contact, i.e. touching one another; Means for effecting or maintaining such contact; Electrically-conductive connections having two or more spaced connecting locations for conductors and using contact members penetrating insulation
    • H01R4/58Electrically-conductive connections between two or more conductive members in direct contact, i.e. touching one another; Means for effecting or maintaining such contact; Electrically-conductive connections having two or more spaced connecting locations for conductors and using contact members penetrating insulation characterised by the form or material of the contacting members
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01RELECTRICALLY-CONDUCTIVE CONNECTIONS; STRUCTURAL ASSOCIATIONS OF A PLURALITY OF MUTUALLY-INSULATED ELECTRICAL CONNECTING ELEMENTS; COUPLING DEVICES; CURRENT COLLECTORS
    • H01R9/00Structural associations of a plurality of mutually-insulated electrical connecting elements, e.g. terminal strips or terminal blocks; Terminals or binding posts mounted upon a base or in a case; Bases therefor
    • HELECTRICITY
    • H05ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05KPRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
    • H05K3/00Apparatus or processes for manufacturing printed circuits
    • H05K3/30Assembling printed circuits with electric components, e.g. with resistor
    • H05K3/32Assembling printed circuits with electric components, e.g. with resistor electrically connecting electric components or wires to printed circuits
    • H05K3/34Assembling printed circuits with electric components, e.g. with resistor electrically connecting electric components or wires to printed circuits by soldering
    • H05K3/3457Solder materials or compositions; Methods of application thereof
    • H05K3/3463Solder compositions in relation to features of the printed circuit board or the mounting process
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2224/00Indexing scheme for arrangements for connecting or disconnecting semiconductor or solid-state bodies and methods related thereto as covered by H01L24/00
    • H01L2224/01Means for bonding being attached to, or being formed on, the surface to be connected, e.g. chip-to-package, die-attach, "first-level" interconnects; Manufacturing methods related thereto
    • H01L2224/42Wire connectors; Manufacturing methods related thereto
    • H01L2224/44Structure, shape, material or disposition of the wire connectors prior to the connecting process
    • H01L2224/45Structure, shape, material or disposition of the wire connectors prior to the connecting process of an individual wire connector
    • H01L2224/45001Core members of the connector
    • H01L2224/45099Material
    • H01L2224/451Material with a principal constituent of the material being a metal or a metalloid, e.g. boron (B), silicon (Si), germanium (Ge), arsenic (As), antimony (Sb), tellurium (Te) and polonium (Po), and alloys thereof
    • H01L2224/45138Material with a principal constituent of the material being a metal or a metalloid, e.g. boron (B), silicon (Si), germanium (Ge), arsenic (As), antimony (Sb), tellurium (Te) and polonium (Po), and alloys thereof the principal constituent melting at a temperature of greater than or equal to 950°C and less than 1550°C
    • H01L2224/45144Gold (Au) as principal constituent
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2224/00Indexing scheme for arrangements for connecting or disconnecting semiconductor or solid-state bodies and methods related thereto as covered by H01L24/00
    • H01L2224/80Methods for connecting semiconductor or other solid state bodies using means for bonding being attached to, or being formed on, the surface to be connected
    • H01L2224/81Methods for connecting semiconductor or other solid state bodies using means for bonding being attached to, or being formed on, the surface to be connected using a bump connector
    • H01L2224/818Bonding techniques
    • H01L2224/81801Soldering or alloying
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2924/00Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
    • H01L2924/01Chemical elements
    • H01L2924/01029Copper [Cu]
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2924/00Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
    • H01L2924/01Chemical elements
    • H01L2924/01033Arsenic [As]
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2924/00Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
    • H01L2924/01Chemical elements
    • H01L2924/01047Silver [Ag]
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2924/00Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
    • H01L2924/01Chemical elements
    • H01L2924/0105Tin [Sn]
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2924/00Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
    • H01L2924/01Chemical elements
    • H01L2924/01079Gold [Au]
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2924/00Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
    • H01L2924/01Chemical elements
    • H01L2924/01082Lead [Pb]
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10TTECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T29/00Metal working
    • Y10T29/49Method of mechanical manufacture
    • Y10T29/49002Electrical device making
    • Y10T29/49117Conductor or circuit manufacturing
    • Y10T29/49121Beam lead frame or beam lead device
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10TTECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T29/00Metal working
    • Y10T29/49Method of mechanical manufacture
    • Y10T29/49002Electrical device making
    • Y10T29/49117Conductor or circuit manufacturing
    • Y10T29/49174Assembling terminal to elongated conductor

Definitions

  • connections thus made offer mediocre reliability beyond two or three connections per millimeter, so that their use cannot be contemplated in metal, said amalgam being topped by a thin film of mercury in the form of a meniscus with a small curvature,
  • the process of the invention may be applied advantageously to the connection of microcircuit members, such as the terminal lugs and the conductors, making the establishment of contacts between them and their disconnection particularly easy.
  • the coating metal selected here is gold, silver, or any other metal capable of forming a stable and solid amalgam with mercury, under the conditions under which the connection members are used.
  • the formation of the amalgam and the mercury meniscus on the members may be accomplished by simple immersion of these members in a bath of mercury for a very short period of time.
  • This invention is intended to provide a method for obtaining electrical connection members enabling us to achieve considerable connection density, something which is particularly desirable in microcircuits, while guaranteeing a high degree of reliability, even at low temperatures.
  • the method involved in this invention is characterized by the fact that we cover each of the conducting members to be connected with a thin layer of at least one metal capable of constituting an amalgam with mercury and that we then establish, on each of said members, an amalgam covered by a thin film of mercury in the form of a meniscus with a small curvature, obtained by placing each of these members in contact with a surplus of mercury with respect to the quantity strictly necessary for the establishment of the amalgam, the connection being then accomplished by the simple juxtaposition of the mercury meniscuses formed, respectively, on the members to be connected.
  • the invention also, by way of a new industrial product, concerns an electrical connection member characterized by the fact that it essentially involves a conducting body on which is deposed an amalgam formed between the mercury and at least one coatingstick to the conductor. For example, for a cylindrical conducting wire with a certain diameter, it is advisable to deposit metal with a thickness in excess of 0.1 mu.
  • the invention offers the following advantages,
  • FIG. 2 shows the two bare conductors in a cross-section after the connection has been established.
  • a microcircuit which includes a substrate 1, on which are arranged the terminal lugs, such as 2, made up of a layer of chrome. We cover this deposit of chrome with a thin layer of gold 3, particularly through evaporation or pulverization in a vacuum.
  • the outside conductor is made up of a layer ofv copper 4, covered successively by a layer of copper 5 and a thin layer of gold 6.
  • the outside conductors can also be made up of wires consisting of gold, 'gold-platedcopper, or any other support covered with gold or silver.
  • the outside conductors can advantageously be maintained in the desired position relative to the terminal-lugs by a very simple mechanical mounting or by any other suitabl means.
  • Method for obtaining non-permanent electrical connections at ambient temperatures comprising coating each of the conducting members to be connected together with a thin layer of a metal capable of constituting an amalgam with mercury, forming, on each of said members, an amalgam topped with a thin film of mercury in the form of a meniscus with a small curvature by placing each of said members in contact with a surplus of mercury with respect to the quantity that is stoichiometrically necessary for the constitution of the amalgam, and juxtaposing the mercury meniscuses formed, respectively, on the members to be connected adjacent each other without applying pressure therebetween.

Landscapes

  • Engineering & Computer Science (AREA)
  • Microelectronics & Electronic Packaging (AREA)
  • Manufacturing & Machinery (AREA)
  • Mechanical Engineering (AREA)
  • Computer Hardware Design (AREA)
  • Power Engineering (AREA)
  • Connections Effected By Soldering, Adhesion, Or Permanent Deformation (AREA)
  • Manufacturing Of Electrical Connectors (AREA)
US59397A 1969-07-31 1970-07-30 Method for obtaining electrical connections, especially for microcircuits Expired - Lifetime US3702500A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
FR6926367A FR2052245A5 (xx) 1969-07-31 1969-07-31

Publications (1)

Publication Number Publication Date
US3702500A true US3702500A (en) 1972-11-14

Family

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Family Applications (1)

Application Number Title Priority Date Filing Date
US59397A Expired - Lifetime US3702500A (en) 1969-07-31 1970-07-30 Method for obtaining electrical connections, especially for microcircuits

Country Status (3)

Country Link
US (1) US3702500A (xx)
DE (1) DE2037630A1 (xx)
FR (1) FR2052245A5 (xx)

Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3869787A (en) * 1973-01-02 1975-03-11 Honeywell Inf Systems Method for precisely aligning circuit devices coarsely positioned on a substrate
US4044816A (en) * 1975-06-19 1977-08-30 Theodore H. Krueger Formation of metal parts
US4739917A (en) * 1987-01-12 1988-04-26 Ford Motor Company Dual solder process for connecting electrically conducting terminals of electrical components to printed circuit conductors
EP0385142A2 (en) * 1989-02-28 1990-09-05 Fujitsu Limited Electrical connecting apparatus
US5007163A (en) * 1990-04-18 1991-04-16 International Business Machines Corporation Non-destructure method of performing electrical burn-in testing of semiconductor chips
US5038996A (en) * 1988-10-12 1991-08-13 International Business Machines Corporation Bonding of metallic surfaces
US5192835A (en) * 1990-10-09 1993-03-09 Eastman Kodak Company Bonding of solid state device to terminal board
US5269453A (en) * 1992-04-02 1993-12-14 Motorola, Inc. Low temperature method for forming solder bump interconnections to a plated circuit trace
US7348494B1 (en) * 2000-12-15 2008-03-25 Nortel Networks Limited Signal layer interconnects
US20080185175A1 (en) * 2007-02-06 2008-08-07 Shinko Electric Industries Co., Ltd. Multilayer wiring board and method of manufacturing the same
US20100282501A1 (en) * 2006-05-25 2010-11-11 Fujikura Ltd. Printed wiring board, method for forming the printed wiring board, and board interconnection structure

Citations (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1170388A (en) * 1911-09-07 1916-02-01 Hermann Anschuetz-Kaempfe Electrical contact.
US1792973A (en) * 1928-12-04 1931-02-17 Harry J Frenz Electrical socket
US2354081A (en) * 1940-01-20 1944-07-18 Gen Electric Method of forming contacts
US2655641A (en) * 1948-10-29 1953-10-13 Aircraft Marine Prod Inc Electrical connector having a mercury amalgam coating on its inner surface
US2735050A (en) * 1952-10-22 1956-02-14 Liquid soldering process and articles
US2737711A (en) * 1954-12-13 1956-03-13 Mansfield Sanitary Pottery Inc Method of assembling ball cocks and the like
US2846762A (en) * 1955-02-17 1958-08-12 David E Walker Metal plating process
US2947939A (en) * 1956-09-24 1960-08-02 Libbey Owens Ford Glass Co Testing electrically conductive articles
US3110089A (en) * 1959-12-16 1963-11-12 Engelhard Ind Inc Method of bonding amalgam inserts in cavities and structure thereby produced
US3165403A (en) * 1962-03-27 1965-01-12 Gen Electric Superconductive materials
US3622944A (en) * 1969-08-05 1971-11-23 Tokai Denki Kk Electrical connector

Patent Citations (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1170388A (en) * 1911-09-07 1916-02-01 Hermann Anschuetz-Kaempfe Electrical contact.
US1792973A (en) * 1928-12-04 1931-02-17 Harry J Frenz Electrical socket
US2354081A (en) * 1940-01-20 1944-07-18 Gen Electric Method of forming contacts
US2655641A (en) * 1948-10-29 1953-10-13 Aircraft Marine Prod Inc Electrical connector having a mercury amalgam coating on its inner surface
US2735050A (en) * 1952-10-22 1956-02-14 Liquid soldering process and articles
US2737711A (en) * 1954-12-13 1956-03-13 Mansfield Sanitary Pottery Inc Method of assembling ball cocks and the like
US2846762A (en) * 1955-02-17 1958-08-12 David E Walker Metal plating process
US2947939A (en) * 1956-09-24 1960-08-02 Libbey Owens Ford Glass Co Testing electrically conductive articles
US3110089A (en) * 1959-12-16 1963-11-12 Engelhard Ind Inc Method of bonding amalgam inserts in cavities and structure thereby produced
US3165403A (en) * 1962-03-27 1965-01-12 Gen Electric Superconductive materials
US3622944A (en) * 1969-08-05 1971-11-23 Tokai Denki Kk Electrical connector

Cited By (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3869787A (en) * 1973-01-02 1975-03-11 Honeywell Inf Systems Method for precisely aligning circuit devices coarsely positioned on a substrate
US4044816A (en) * 1975-06-19 1977-08-30 Theodore H. Krueger Formation of metal parts
US4739917A (en) * 1987-01-12 1988-04-26 Ford Motor Company Dual solder process for connecting electrically conducting terminals of electrical components to printed circuit conductors
US5038996A (en) * 1988-10-12 1991-08-13 International Business Machines Corporation Bonding of metallic surfaces
EP0385142A2 (en) * 1989-02-28 1990-09-05 Fujitsu Limited Electrical connecting apparatus
EP0385142A3 (en) * 1989-02-28 1991-02-06 Fujitsu Limited Electrical connecting apparatus
US5007163A (en) * 1990-04-18 1991-04-16 International Business Machines Corporation Non-destructure method of performing electrical burn-in testing of semiconductor chips
US5192835A (en) * 1990-10-09 1993-03-09 Eastman Kodak Company Bonding of solid state device to terminal board
US5269453A (en) * 1992-04-02 1993-12-14 Motorola, Inc. Low temperature method for forming solder bump interconnections to a plated circuit trace
US7348494B1 (en) * 2000-12-15 2008-03-25 Nortel Networks Limited Signal layer interconnects
US20100282501A1 (en) * 2006-05-25 2010-11-11 Fujikura Ltd. Printed wiring board, method for forming the printed wiring board, and board interconnection structure
US20100282499A1 (en) * 2006-05-25 2010-11-11 Fujikura Ltd. Printed wiring board, method for forming the printed wiring board, and board interconnection structure
US8222531B2 (en) * 2006-05-25 2012-07-17 Fujikura Ltd. Printed wiring board, method for forming the printed wiring board, and board interconnection structure
US8492657B2 (en) * 2006-05-25 2013-07-23 Fujikura Ltd. Printed wiring board, method for forming the printed wiring board, and board interconnection structure
US20080185175A1 (en) * 2007-02-06 2008-08-07 Shinko Electric Industries Co., Ltd. Multilayer wiring board and method of manufacturing the same
US8026448B2 (en) * 2007-02-06 2011-09-27 Shinko Electric Industries Co., Ltd. Multilayer wiring board and method of manufacturing the same

Also Published As

Publication number Publication date
FR2052245A5 (xx) 1971-04-09
DE2037630A1 (de) 1971-02-11

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