Classifications

• • 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
  • H05K3/00—Apparatus or processes for manufacturing printed circuits
  • H05K3/30—Assembling printed circuits with electric components, e.g. with resistors
  • H05K3/303—Assembling printed circuits with electric components, e.g. with resistors with surface mounted components
  • H05K3/305—Affixing by adhesive
• • 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
  • H05K13/00—Apparatus or processes specially adapted for manufacturing or adjusting assemblages of electric components
  • H05K13/04—Mounting of components, e.g. of leadless components
  • H05K13/046—Surface mounting
  • H05K13/0469—Surface mounting by applying a glue or viscous material
• • 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
  • H05K1/00—Printed circuits
  • H05K1/02—Details
  • H05K1/03—Use of materials for the substrate
  • H05K1/0306—Inorganic insulating substrates, e.g. ceramic, glass
• • 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
  • H05K2201/00—Indexing scheme relating to printed circuits covered by H05K1/00
  • H05K2201/10—Details of components or other objects attached to or integrated in a printed circuit board
  • H05K2201/10613—Details of electrical connections of non-printed components, e.g. special leads
  • H05K2201/10621—Components characterised by their electrical contacts
  • H05K2201/10689—Leaded Integrated Circuit [IC] package, e.g. dual-in-line [DIL]
• • 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
  • H05K2201/00—Indexing scheme relating to printed circuits covered by H05K1/00
  • H05K2201/10—Details of components or other objects attached to or integrated in a printed circuit board
  • H05K2201/10613—Details of electrical connections of non-printed components, e.g. special leads
  • H05K2201/10954—Other details of electrical connections
  • H05K2201/10984—Component carrying a connection agent, e.g. solder, adhesive
• • 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
  • H05K2203/00—Indexing scheme relating to apparatus or processes for manufacturing printed circuits covered by H05K3/00
  • H05K2203/01—Tools for processing; Objects used during processing
  • H05K2203/0104—Tools for processing; Objects used during processing for patterning or coating
  • H05K2203/0113—Female die used for patterning or transferring, e.g. temporary substrate having recessed pattern
• • 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
  • H05K2203/00—Indexing scheme relating to apparatus or processes for manufacturing printed circuits covered by H05K3/00
  • H05K2203/01—Tools for processing; Objects used during processing
  • H05K2203/0104—Tools for processing; Objects used during processing for patterning or coating
  • H05K2203/0143—Using a roller; Specific shape thereof; Providing locally adhesive portions thereon
• • 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
  • H05K2203/00—Indexing scheme relating to apparatus or processes for manufacturing printed circuits covered by H05K3/00
  • H05K2203/02—Details related to mechanical or acoustic processing, e.g. drilling, punching, cutting, using ultrasound
  • H05K2203/0278—Flat pressure, e.g. for connecting terminals with anisotropic conductive adhesive
• • 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
  • H05K2203/00—Indexing scheme relating to apparatus or processes for manufacturing printed circuits covered by H05K3/00
  • H05K2203/05—Patterning and lithography; Masks; Details of resist
  • H05K2203/0502—Patterning and lithography
  • H05K2203/0537—Transfer of pre-fabricated insulating pattern
• • 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
  • H05K3/00—Apparatus or processes for manufacturing printed circuits
  • H05K3/10—Apparatus or processes for manufacturing printed circuits in which conductive material is applied to the insulating support in such a manner as to form the desired conductive pattern
  • H05K3/12—Apparatus or processes for manufacturing printed circuits in which conductive material is applied to the insulating support in such a manner as to form the desired conductive pattern using thick film techniques, e.g. printing techniques to apply the conductive material or similar techniques for applying conductive paste or ink patterns
  • H05K3/1216—Apparatus or processes for manufacturing printed circuits in which conductive material is applied to the insulating support in such a manner as to form the desired conductive pattern using thick film techniques, e.g. printing techniques to apply the conductive material or similar techniques for applying conductive paste or ink patterns by screen printing or stencil printing
• • Y—GENERAL 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
  • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
  • Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
  • Y02P70/00—Climate change mitigation technologies in the production process for final industrial or consumer products
  • Y02P70/50—Manufacturing or production processes characterised by the final manufactured product

Definitions

• the present invention relates to electronic circuit assembly. Integrated circuits are to be found in more and more electronic equipment to the extent that circuit boards in ⁇ corporating integrated circuits alone are now in common use.
• the traditional manner of pre-assembling electronic compo ⁇ nents, including integrated circuits, to circuit boards, fo instance etched-copper printed-circuit boards has been to pre-assemble a component to a board by passing its contacts through board apertures and bending over at least some of the contacts to mechanically retain the component on the board. Subsequently, the contacts are soldered to the copper circuit strips.
• hybrid 1 circuits have started to be used. Such a circuit comprises a number of simple inte ⁇ grated circuits which are cheaper to use than a single more complex integrated circuit.
• the integrated circuits in a "hybrid 1 are usually connected to a "ceramic substrate” board which typically may have five layers of silk-screen deposited contact strips built-up on the substrate. For making contact with the contacts of such a board, the con ⁇ tacts of integrated circuits do not pass through board apertures but abut the board contacts at the ends of the components' contacts which are bent over as feet.
• the sets of contacts are soldered together, typically either in a solder wave wherein the board is inverted and passed over a solder wave, or in a vapour phase soldering installation wherein previously applied, e.g. by silk screening, solder cream is caused to fuse in an oven.
• soldering rely upon the integrated circuit components being mechanically fixed to the board.
• Such fixing is presently effected by adhering of the components in position with epoxy resin adhesive.
• Such adhesive has disadvantages. If too fast curing adhesive is used problems can be experienced with the appli ⁇ cation gun becoming clogged with already cured adhesive. The alternative is to use a slower curing adhesive. This has disadvantages in that if speeding up of production is required, the adhesive can be caused to cure by heating but this requires passage of the pre-assembled components and board through an adhesive-curing oven.
• the object of the present invention is to improve the assembly of electronic- circuits in respect of the adhering of electronic components to carriers.
• the term "electronic components” is intended to include not only integrated circuits but also associated components such as transistors, diodes, capaci- tors, resistors and inductors.
• integrated circuit includes not only integrated circuit chips incorporated in bodies moulded with sizes and contact numbers to suit the specific chips, as is U.K. practice, but also integrated circuit chips wired into standardized chip carriers, as is U.S. practice.
• chip carrier should not be confused with the term circuit carrier or "carrier” as defined below.
• carrier is intended to in ⁇ clude conventional printed circuit boards, ceramic substrate boards and any other form of board or like planar member provided with contacts to which two or more electronic components' contacts are to be connected as by soldering.
• a method of preparing an electronic component carrier comprising providing a carrier with surface contacts for connection to a plurality of electronic components, and pre-applying adhesive to substantially all the areas of the carrier surface, to which electronic components are to be mounted to be connected to the contacts.
• all the areas to receive components will have adhesive pre-applied in this aspect of the invention, one or two of the areas for typically six components per carrier may not have adhesive pre-applied fo special reasons peculiar to the carrier and/or component(s) concerned.
• the pre- application of the adhesive is an essentially separate operation from the positioning of the components.
• the adhesive may be pre-applied in an integrated pro ⁇ duction line as the step immediately prior or a few steps prior to the positioning of the or the first of the com- ponents upon their respective areas of free surface of adhesive to adhere the components in place on the carrier.
• the positioning of the components may be carried out in another production line, possibly in a separate premises. It is envisaged that the components may be applied singly either manually or automatically or together usually automatically.
• Soldering, or analogous connection, for final assembly of the components to the carrier will normally be carried out immediately after positioning of the components.
• the invention also includes the products of the method of the first aspect of the inventon, namely a carrier having a pre-applied adhesive both with and without components positioned thereon.
• a release backing material will normally be applied to the pre-applied adhesive.
• the backing may ' be in strip form with an array of carriers adhered thereto.
• the adhesive will be such as not to cure and/or lose its tackiness until the release backing is removed therefrom. Accordingly it is envisaged that in this technical application for the in ⁇ vention the adhesive will be a resin modified acrylic pressure sensitive adhesive. Nevertheless it is antici ⁇ pated that other adhesives may be suitable.
• the adhesive should be such as not to lose effec ⁇ tiveness at soldering temperatures. However since the whole component being soldered does not reach the soldering tempe- rature, adhesives which would normally lose effectiveness when heated evenly to soldering temperatures may be used. It is preferred that once “pre-applied” the adhesive should have a "flat format” preferably with clearly defined limits so as not to encroach on the carrier's contacts.
• flat format adhesive is to be understood an adhesive so applied to present a free surface at least substantially parallel to the surface to which it has been applied. Spray applied liquid adhesive may take up a flat format if the spray droplets are sufficiently small.
• any one of the following adhesive forms may be suitable as flat format adhesives: (i) Two sided adhesive tape cut to shape; (ii) Transferable adhesive film applied from a backing tape, the film either being cut to shape possibly with its backing tape or being pre-shaped on the backing tape. Where the pre-shaping and pre- positioning of adhesive film is sufficiently accurate, the carrier may be offered directly to the adhesive. The backing tape may then become the release backing mentioned above;
• the preferred method of pre-applying adhesive is by screen printing. This necessitates the adhesive being in liquid form during the pre-application step. Thereafter the adhesive's solvent may be allowed to evaporate off at room temperature where the adhesive is solvent based, turni the adhesive into a solid or a gel. This is a slow proces typically taking one hour where the solvent is water. Evaporation can be speeded by passing the carriers through thermal oven after pre-application of the adhesive. Such heat accelerated evaporation is still slow, typically takin 5 minutes, in comparison with the screen printing speeds obtainable.
• Pressure sensitive adhesives are under development which cure by undergoing a molecular change involving cross linking between polymer chains. This change from liquid t a solid or a gel- occurs on exposure to ultra violet light.
• Such an adhesive is preferred.
• the latter After pre-application of the adhesive to the carriers by screen printing, the latter are passed through an "ultra violet tunnel" in which they are subjected to ultra violet light so as to cause the adhesive to solidify or gel. Typically this curing takes less than h minute. This speed is important, since it enables the carriers to pass from a station at which the adhesive is pre-applied to a station at which they are exposed to ultra violet light, the application of this adhesive and the exposure -to ultra violet light occurring synchronously to components at the respective stations.
• An alternative, within the concept of the present invention, is that the electronic components as opposed to the carrier may have .the adhesive pre-applied to them, by analogous, preferably "flat format" means.
• a method of preparing a plurality of electronic components for mounting upon a carrier as hereinbefore defined comprising applying adhesive to a flat surface of the component, which surface of the component is to abut the carrier surface, with the interposition of the adhesive.
• the pre-applied-adhesive electronic compo ⁇ nents are temporarily adhered to a release backing.
• the release backing may be incorporated in a sealed strip-like container, either totally within the container or forming part of the container.
• the invention also includes the products of the second aspect of the invention, namely components having adhesive pre-applied to them, both before and after positioning on a carrier.
• Figure 1 is a plan view of a carrier with adhesive pre- applied in accordance with the invention
• Figure 2 is a side view of the carrier of Figure 1 with electronic components pre-assembled thereto;
• Figure 3 is a diagrammatic side view of carriers being offered up to a tape carrying discreet adhesive film por ⁇ tions;
• Figure 4 is a diagrammatic side view of adhesive being pre-applied to carriers by a roller;
• Figure 5 is a diagrammatic side view of adhesive being applied to electronic components and the components being temporarily adhered to a release tape
• Figure 6 is a diagrammatic side view of the components and release tape of Figure 5 being encapsulated in strip form;
• Figure 7 is a side view of the components of Figure 5 being pre-assembled to a carrier; and Figure 8 is a diagrammatic side view of carriers passing a screen printing station and an ultra violet tunnel.
• the carrier 1 of Figure 1 is a ceramic substrate car ⁇ rier and has the usual contact pins 2 and component contacts 3.
• rectangles 4 of flat format adhesive have been pre-applied by a silk-screen process.
• the outline of the rectangles exactly corresponds to the outline of the components 5, see Figure 2, to be applied.
• Figure 2 shows the components 5, integrated circuits in this "hybrid" circuit, positioned in place on the flat format adhesive rectangles 4 and thus adhered to the carrier with their contacts 6 aligned with the carrier's contacts 3 for subsequent soldering.
• FIG. 3 shows carriers 31 being offered up by an in ⁇ dexing wheel 7 to a waxed release tape 8 having portions 34 of adhesive to be pre-applied to the carriers 31.
• the carriers may be fed manually or automatically to the in ⁇ dexing wheel where they are retained by any suitable means such as by suction until they are opposite a pressure roller 9 which adheres the carriers to the adhesive. As the indexing wheel rotates further the vacuum for the carrier passing the roller 9 is released leaving the carrier tem ⁇ porarily adhered to the release tape 8.
• Both lateral positioning of the tape and the adhesive portions 34 and longitudinal positioning with respect to the carriers in the indexing wheel 7 is controlled by gearing of the wheel 7 to sprockets 10 engaging in sprocket holes running along each side of the tape. Hence the portions 34 are correctly positioned on the carriers.
• Figure 4 shows an alternative arrangement for pre- applying adhesive portions 44 to carriers 41 via a roller
• the carriers 41 pass under the roller 11 on a conveyor system 12 in synchronism with the roller 11.
• Adhesive is applied to the roller 11 by feed rollers 12 and aportioned on the roller 11 by an apertured portioning roller 13 having recesses 14 corresponding to the dimensions of adhesive portions 44 to be applied to the carriers 41.
• the roller 11 rotates, it transfers the aportioned adhesive to the carriers 41 passing under it.
• Figure 5 shows a similar arrangement for pre-applying adhesive 54 to electronic components 55. Since the com ⁇ ponents are to have their entire surface 15 to be adhered to a carrier pre-applied with adhesive, the applying roller 16 does not require a portioning roller but merely adhesive feed rollers 12. The components 55 are passed under the adhesive applying roller 16 for transfer of adhesive there ⁇ to. To avoid any possibility of adhesive reaching the components' contacts 56 the roller 16 is wide enough to apply adhesive to the bodies only of the components. Downstream of the roller 16 a release backing 17 is fed from a roll 18 onto the pre-applied adhesive 54.
• Figure 6 shows the release backing 17 together with its temporarily adhered components 55 is fed between two strips of plastics material film 19,20 which are formed into an encapsulating strip 21 by a pair of forming and sealing rollers 22.
• Figure 7 shows a carrier 71 with no pre-applied adhe ⁇ sive onto which one pre-applied adhesive 54 carrying compo ⁇ nent 51' has already been pre-assembled and adhered in place; and another such component 51" is in the process of being positioned.
• Figure 8 shows the pre-application of ultra violet light curing adhesive 82 to carriers 81.
• a conveyor 83 having carrier receptacles 85, moves through (i) a carrier placing station 86 at which a carrier 81 is placed on the conveyor, (ii) a pre-application station 87 and (iii) a OV station 88.
• the adhesive 82 is screen printed through a screen 88 with a wiper 89 onto the carrier 81 at the station to form an adhesive portion 84.
• the adhesive portion 84 on the respective carrier 81 is irradiated with ultra violet light from a UV lamp 90, to cause it to solidify or gel.
• a release backing is applied at the next station (not shown) in the manner of release backing 17 shown in Figure 5.
• the carrier 83 moves on a lock/stop basis typically every h minute whereby the operations at each station occur synchronously.
• the use of UV curing adhesive is particularly advantageous in that it cures at the OV station 88 in the cycle-time taken for the operations at the other stations.
• the adhesive may be pre- applied by a silk-screen process.
• the release backing may be apertured to permit screen printing of solder cream after the adhesive has been pre-applied.

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• Engineering & Computer Science (AREA)
• Manufacturing & Machinery (AREA)
• Microelectronics & Electronic Packaging (AREA)
• Electric Connection Of Electric Components To Printed Circuits (AREA)
• Supply And Installment Of Electrical Components (AREA)

Applications Claiming Priority (2)

Publications (1)

Family

ID=10549343

Family Applications (1)

Country Status (6)

Families Citing this family (9)

Family Cites Families (14)

• 1983
  • 1983-09-27 GB GB08325803A patent/GB2147148A/en not_active Withdrawn
• 1984
  • 1984-09-27 WO PCT/GB1984/000330 patent/WO1985001634A1/en not_active Ceased
  • 1984-09-27 JP JP59503532A patent/JPS61500047A/ja active Pending
  • 1984-09-27 EP EP84903558A patent/EP0159331A1/en not_active Withdrawn
• 1985
  • 1985-05-17 KR KR1019850700044A patent/KR850700100A/ko not_active Withdrawn
  • 1985-05-23 DK DK229285A patent/DK229285A/da not_active Application Discontinuation

Non-Patent Citations (1)

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