GB1589642A - Electronic circuit assemblies - Google Patents

Electronic circuit assemblies Download PDF

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Publication number
GB1589642A
GB1589642A GB1637977A GB1637977A GB1589642A GB 1589642 A GB1589642 A GB 1589642A GB 1637977 A GB1637977 A GB 1637977A GB 1637977 A GB1637977 A GB 1637977A GB 1589642 A GB1589642 A GB 1589642A
Authority
GB
United Kingdom
Prior art keywords
circuit board
package
connector
printed circuit
pads
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
Application number
GB1637977A
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.)
Fujitsu Services Ltd
Original Assignee
Fujitsu Services Ltd
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 Fujitsu Services Ltd filed Critical Fujitsu Services Ltd
Priority to GB1637977A priority Critical patent/GB1589642A/en
Priority to FR7811742A priority patent/FR2388458A1/en
Publication of GB1589642A publication Critical patent/GB1589642A/en
Expired legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L24/00—Arrangements for connecting or disconnecting semiconductor or solid-state bodies; Methods or apparatus related thereto
    • H01L24/80—Methods for connecting semiconductor or other solid state bodies using means for bonding being attached to, or being formed on, the surface to be connected
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L23/00—Details of semiconductor or other solid state devices
    • H01L23/34—Arrangements for cooling, heating, ventilating or temperature compensation ; Temperature sensing arrangements
    • H01L23/36—Selection of materials, or shaping, to facilitate cooling or heating, e.g. heatsinks
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L23/00—Details of semiconductor or other solid state devices
    • H01L23/52—Arrangements for conducting electric current within the device in operation from one component to another, i.e. interconnections, e.g. wires, lead frames
    • H01L23/538—Arrangements for conducting electric current within the device in operation from one component to another, i.e. interconnections, e.g. wires, lead frames the interconnection structure between a plurality of semiconductor chips being formed on, or in, insulating substrates
    • H01L23/5385—Assembly of a plurality of insulating substrates
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L25/00—Assemblies consisting of a plurality of individual semiconductor or other solid state devices ; Multistep manufacturing processes thereof
    • H01L25/03—Assemblies consisting of a plurality of individual semiconductor or other solid state devices ; Multistep manufacturing processes thereof all the devices being of a type provided for in the same subgroup of groups H01L27/00 - H01L33/00, or in a single subclass of H10K, H10N, e.g. assemblies of rectifier diodes
    • H01L25/10—Assemblies consisting of a plurality of individual semiconductor or other solid state devices ; Multistep manufacturing processes thereof all the devices being of a type provided for in the same subgroup of groups H01L27/00 - H01L33/00, or in a single subclass of H10K, H10N, e.g. assemblies of rectifier diodes the devices having separate containers
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01R—ELECTRICALLY-CONDUCTIVE CONNECTIONS; STRUCTURAL ASSOCIATIONS OF A PLURALITY OF MUTUALLY-INSULATED ELECTRICAL CONNECTING ELEMENTS; COUPLING DEVICES; CURRENT COLLECTORS
    • H01R12/00—Structural 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
    • H01R12/70—Coupling devices
    • H01R12/71—Coupling devices for rigid printing circuits or like structures
    • H01R12/712—Coupling 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
    • H01R12/714—Coupling 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
    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
    • H05K7/00—Constructional details common to different types of electric apparatus
    • H05K7/02—Arrangements of circuit components or wiring on supporting structure
    • H05K7/10—Plug-in assemblages of components, e.g. IC sockets
    • H05K7/1053—Plug-in assemblages of components, e.g. IC sockets having interior leads
    • H05K7/1061—Plug-in assemblages of components, e.g. IC sockets having interior leads co-operating by abutting
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2924/00—Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
    • H01L2924/01—Chemical elements
    • H01L2924/01013—Aluminum [Al]
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2924/00—Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
    • H01L2924/01—Chemical elements
    • H01L2924/01023—Vanadium [V]
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2924/00—Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
    • H01L2924/01—Chemical elements
    • H01L2924/01033—Arsenic [As]
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2924/00—Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
    • H01L2924/01—Chemical elements
    • H01L2924/01049—Indium [In]
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2924/00—Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
    • H01L2924/01—Chemical elements
    • H01L2924/01074—Tungsten [W]
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2924/00—Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
    • H01L2924/01—Chemical elements
    • H01L2924/01082—Lead [Pb]
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2924/00—Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
    • H01L2924/013—Alloys
    • H01L2924/014—Solder alloys
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2924/00—Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
    • H01L2924/10—Details of semiconductor or other solid state devices to be connected
    • H01L2924/11—Device type
    • H01L2924/14—Integrated circuits

Landscapes

  • Engineering & Computer Science (AREA)
  • Microelectronics & Electronic Packaging (AREA)
  • Power Engineering (AREA)
  • Computer Hardware Design (AREA)
  • Physics & Mathematics (AREA)
  • Condensed Matter Physics & Semiconductors (AREA)
  • General Physics & Mathematics (AREA)
  • Chemical & Material Sciences (AREA)
  • Materials Engineering (AREA)
  • Structures For Mounting Electric Components On Printed Circuit Boards (AREA)
  • Cooling Or The Like Of Electrical Apparatus (AREA)

Description

(54) IMPROVEMENTS IN OR RELATING TO ELECTRONIC CIRCUIT ASSEMBLIES (71) We, INTERNATIONAL COMPUTERS lIMITED, a British Company, of ICL House, Putney, London. S.W.15, do hereby declare the invention for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement: This invention relates to electronic circuit assemblies.
In one common form of circuit assembly, integrated circuit components are mounted on a printed circuit board, with forced air cooling.
The components may, for example, be in the form of dual-in-line packages, having terminal leads which are soldered to the circuit board.
Such assemblies provide a high density of components and are widely used for medium and small scale integrated circuits. However, this form of circuit assembly has been found not to be suitable in the case of large scale integrated circuit (LSI) components, where the power dissipation from each component is relatively high.
One object of the invention is to provide a novel form of circuit assembly which is especially suitable for LSI components.
According to the invention, there is provided an electronic circuit assembly comprising a printed circuit board; at least one integrated chip package including a metal heat sink member defining a wall to the package on the side thereof which is remote from the circuit board and to which the chip is bonded, and contact pads on the side thereof that is adjacent to the printed circuit board said pads being electrically connected to the terminals of the chip, said assembly also including at least one electrical connector incorporating resiliently compressible regions for exerting contact pressure when located between the package and the circuit board.
For a better understanding of the invention and to show how to carry the same into effect, reference will now be made to the accompanying drawings in which: Figure 1 illustrates a first embodiment of a circuit assembly; Figure 2 is a plan view of one of the circuit packages of Figure 1; Figure 3 illustrates a first modification of the circuit assembly of Figure 1; Figure 4 is a longitudinal section of a second embodiment of a circuit assembly; Figure 5 is a transverse section on the line V-V of Figure 4; and Figure 6 is a transverse section on the line VI and VI of Figure 4.
Referring to Figure 1, the circuit assembly comprises a printed circuit board 1 and a plurality of LSI chips 2. Each chip 2 is enclosed in a package 3 comprising a metal heat sink member 4 and a ceramic member 5 which is bonded to the metal member. The ceramic member has an aperture 6 in which the chip 2 is located, the chip being bonded to the metal member 4, for example by Indium soldering, to ensure a good thermal contact.
The pads of the chip are contacted by a lead frame 7 (as seen in the plan view Figure 2) which provides a fan-out from the chip pads to a set of contact pads 8 around the edge of the ceramic member 5.
A ceramic lid 9 completes the package, enclosing the chip but leaving the contact pads 8 exposed.
Typically, the package is of the order of 2 cm. square and has 64 contact pads.
Contact between the pads 8 and corresponding pads 10 on the printed circuit board 1 is made by means of connectors 11. One suitable form of connector is described and claimed in our co-pending British Patent Application No. 6638/77 (Serial no.1564561).
This connector comprises a rigid elongated core 12 (e.g. formed as an extrusion of aluminium) having four grooves 13 in which are seated four elastomeric cylinders 14. A thin plastics film 15, carrying a pattern of parallel conductive tracks, is wrapped around the core and cylinders with the conductive tracks facing outwards and running peripherally around the connector so as to form signal paths between the pads 8 on the packages and the pads 10 on the circuit board. The pitch of the conductive tracks is considerably smaller than that of the pads 8, 10 so that alignment of the connectors 11 with the packages and the circuit board is not critical.
The connectors 11 are secured to the circuit board 1 by screws 16, while the packages 3 are secured by means of metal clamp plates 17, (only one shown in Figure), which are screwed to the connectors 11. Thus, the elastomeric rods 14 are compressed between the packages, 3 and the circuit board 1, ensuring a good contact pressure.
In the completed assembly, the metal heat sink members 4 form a curtain wall over which cooling air can flow. This surface may carry cooling fins to assist the heat transfer. Alternatively, liquid cooling means may be attached to this surface.
In the arrangement of Figure 1, each connector 11 is shared between a pair of adjacent circuit packages 3. In an alternative arrangement, shown in Figure 3, there may be only one connector 17 to each package 18, and the clamping plates 19 may, in this case, be screwed directly to the circuit board 20.
In the arrangement shown in Figures 4 to 6, the chip is similarly enclosed in a package 3, including the ceramic member 5 and the heat sink 4. The mode of mounting the chip is as discussed in relation to Figures 1 and 2.
The electrical contact between the package 3 and the printed circuit board is made by way of a connection unit 11 A which is of a construction somewhat different from that of the connector unit 11, in that the end regions of the conductive strip 15 are held in place by a cylindrical locking strip 1 8 such as a plastics rod, tube or cylinder which snaps into a suitably shaped groove 19 and the member 12.
In addition, the chip package and the connector 1 1 A are held in place by resilient clamp plates 20 which are engageable with pins or dowels 21 mounted on the printed circuit board. To accommodate the pins the package metal base 4 is provided with two downwardly directed bosses 22 located one to each end of the package. In addition, the connection element is apertured to accept the bosses 22.
The upper length pins are of reduced diameter thereby to provide a collar part 23 and a head 24. The collar part is intended to provide a location region for the clamp plate 20. The length of the pin is such that when the plate 20 is engaged with the collars 23 of the pins 21. The package 3 is pulled sufficiently firmly towards the connector element 12 and thus the printed circuit board 1 as to compress the elastomeric cylinders 11 so as to obtain the desired good electrical contact between the pads 8, the conductive strip 15 and the pads 10 of the printed circuit board.
As to the case of the Figures 1 to 3 embodiments, since the pitch of the conductive tracks is considerably smaller than that of the pads 8 and 10 the alignment of the connectors with 6' the packages 3 and the circuit board 1 is not critical.
WHAT WE CLAIM IS: 1. An electronic circuit assembly, comprising a printed circuit board; at least one integrated chip package including a metal heat sink member defining a wall to the package on the side thereof which is remote from the circuit board and to which the chip is bonded, and contact pads on the side thereof that is adjacent to the printed circuit board said pads being electrically connected to the terminals of the chip, said assembly also including at least one electrical connector incorporating resiliently compressible regions for exerting contact pressure when located between the package and the circuit board.
2. An electronic circuit assembly as claimed in Claim 1, and in which the package also includes a ceramic member which is bonded to the metal member, the ceramic member having an aperture for receiving the chip, said contact pads being on the ceramic member; and a non conductive lid for enclosing the chip but leaving the pads exposed.
3. An electronic assembly as claimed in Claim 1 or 2, wherein contact pressure is maintained between the package and the connector, and between the connector and the printed circuit board by a clamping plate which is connected by a locating rod or pin to the printed circuit board.
4. An electronic assembly as claimed in Claim 1 or 2, wherein each said connector is secured to the printed circuit board by a locating screw, and wherein a clamping plate is provided for producing contact pressure between the package and the connector, said clamping plate being supported from a locating pin or rod engaged with the connector.
5. An electronic assembly as claimed in Claim 1 or 2, wherein the package is provided with through bores, for receiving locating rods or pins upstanding from the printed circuit board, the said rods or pins being of such length that the free ends thereof project outwardly of the package, and wherein said free ends mount a resilient clamp plate for holding the package under pressure against the connector.
6. An electronic circuit assembly, constructed and arranged to operate substantially as hereinbefore described with reference to the accompanying drawing.
**WARNING** end of DESC field may overlap start of CLMS **.

Claims (6)

  1. **WARNING** start of CLMS field may overlap end of DESC **.
    tracks is considerably smaller than that of the pads 8, 10 so that alignment of the connectors
    11 with the packages and the circuit board is not critical.
    The connectors 11 are secured to the circuit board 1 by screws 16, while the packages 3 are secured by means of metal clamp plates 17, (only one shown in Figure), which are screwed to the connectors 11. Thus, the elastomeric rods 14 are compressed between the packages, 3 and the circuit board 1, ensuring a good contact pressure.
    In the completed assembly, the metal heat sink members 4 form a curtain wall over which cooling air can flow. This surface may carry cooling fins to assist the heat transfer. Alternatively, liquid cooling means may be attached to this surface.
    In the arrangement of Figure 1, each connector 11 is shared between a pair of adjacent circuit packages 3. In an alternative arrangement, shown in Figure 3, there may be only one connector 17 to each package 18, and the clamping plates 19 may, in this case, be screwed directly to the circuit board 20.
    In the arrangement shown in Figures 4 to 6, the chip is similarly enclosed in a package 3, including the ceramic member 5 and the heat sink 4. The mode of mounting the chip is as discussed in relation to Figures 1 and 2.
    The electrical contact between the package 3 and the printed circuit board is made by way of a connection unit 11 A which is of a construction somewhat different from that of the connector unit 11, in that the end regions of the conductive strip 15 are held in place by a cylindrical locking strip 1 8 such as a plastics rod, tube or cylinder which snaps into a suitably shaped groove 19 and the member 12.
    In addition, the chip package and the connector 1 1 A are held in place by resilient clamp plates 20 which are engageable with pins or dowels 21 mounted on the printed circuit board. To accommodate the pins the package metal base 4 is provided with two downwardly directed bosses 22 located one to each end of the package. In addition, the connection element is apertured to accept the bosses 22.
    The upper length pins are of reduced diameter thereby to provide a collar part 23 and a head 24. The collar part is intended to provide a location region for the clamp plate 20. The length of the pin is such that when the plate 20 is engaged with the collars 23 of the pins 21. The package 3 is pulled sufficiently firmly towards the connector element 12 and thus the printed circuit board 1 as to compress the elastomeric cylinders 11 so as to obtain the desired good electrical contact between the pads 8, the conductive strip 15 and the pads 10 of the printed circuit board.
    As to the case of the Figures 1 to 3 embodiments, since the pitch of the conductive tracks is considerably smaller than that of the pads 8 and 10 the alignment of the connectors with 6' the packages 3 and the circuit board 1 is not critical.
    WHAT WE CLAIM IS: 1. An electronic circuit assembly, comprising a printed circuit board; at least one integrated chip package including a metal heat sink member defining a wall to the package on the side thereof which is remote from the circuit board and to which the chip is bonded, and contact pads on the side thereof that is adjacent to the printed circuit board said pads being electrically connected to the terminals of the chip, said assembly also including at least one electrical connector incorporating resiliently compressible regions for exerting contact pressure when located between the package and the circuit board.
  2. 2. An electronic circuit assembly as claimed in Claim 1, and in which the package also includes a ceramic member which is bonded to the metal member, the ceramic member having an aperture for receiving the chip, said contact pads being on the ceramic member; and a non conductive lid for enclosing the chip but leaving the pads exposed.
  3. 3. An electronic assembly as claimed in Claim 1 or 2, wherein contact pressure is maintained between the package and the connector, and between the connector and the printed circuit board by a clamping plate which is connected by a locating rod or pin to the printed circuit board.
  4. 4. An electronic assembly as claimed in Claim 1 or 2, wherein each said connector is secured to the printed circuit board by a locating screw, and wherein a clamping plate is provided for producing contact pressure between the package and the connector, said clamping plate being supported from a locating pin or rod engaged with the connector.
  5. 5. An electronic assembly as claimed in Claim 1 or 2, wherein the package is provided with through bores, for receiving locating rods or pins upstanding from the printed circuit board, the said rods or pins being of such length that the free ends thereof project outwardly of the package, and wherein said free ends mount a resilient clamp plate for holding the package under pressure against the connector.
  6. 6. An electronic circuit assembly, constructed and arranged to operate substantially as hereinbefore described with reference to the accompanying drawing.
GB1637977A 1977-04-20 1977-04-20 Electronic circuit assemblies Expired GB1589642A (en)

Priority Applications (2)

Application Number Priority Date Filing Date Title
GB1637977A GB1589642A (en) 1977-04-20 1977-04-20 Electronic circuit assemblies
FR7811742A FR2388458A1 (en) 1977-04-20 1978-04-20 ELECTRIC CIRCUIT

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB1637977A GB1589642A (en) 1977-04-20 1977-04-20 Electronic circuit assemblies

Publications (1)

Publication Number Publication Date
GB1589642A true GB1589642A (en) 1981-05-20

Family

ID=10076258

Family Applications (1)

Application Number Title Priority Date Filing Date
GB1637977A Expired GB1589642A (en) 1977-04-20 1977-04-20 Electronic circuit assemblies

Country Status (2)

Country Link
FR (1) FR2388458A1 (en)
GB (1) GB1589642A (en)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4548451A (en) * 1984-04-27 1985-10-22 International Business Machines Corporation Pinless connector interposer and method for making the same

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3638163A (en) * 1970-07-20 1972-01-25 Bell Telephone Labor Inc Connector for electrically interconnecting two parallel surfaces
US3877064A (en) * 1974-02-22 1975-04-08 Amp Inc Device for connecting leadless integrated circuit packages to a printed-circuit board
US3960423A (en) * 1974-10-02 1976-06-01 Amp Incorporated Multi-contact connector for substrate-to-board connections
US3955867A (en) * 1974-10-09 1976-05-11 Burroughs Corporation Integrated circuit package connector with probing facility
US3984166A (en) * 1975-05-07 1976-10-05 Burroughs Corporation Semiconductor device package having lead frame structure with integral spring contacts

Also Published As

Publication number Publication date
FR2388458B1 (en) 1984-07-13
FR2388458A1 (en) 1978-11-17

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Legal Events

Date Code Title Description
PS Patent sealed
PE20 Patent expired after termination of 20 years

Effective date: 19980418