United States Patent [191
`Gloton et al.
`
`[54] METHOD FOR CONTINUOUS ASSEMBLY
`OF PATTERNED STRIPS AND INTEGRATED
`CIRCUIT MICROMODULE OBTAINED BY
`SAID METHOD
`
`[75] Inventors: Jean-Pierre Gloton, Aix en Provence;
`Damien Laroche, Chateauneuf le
`Rouge; Joel Turin, Marseille; Michel
`Fallah, Aubagne, all of France
`
`[73] Assignee: Gemplus Card International,
`Gemenos, France
`
`lllllllllllllllllllllllllllllllgllglulmllllllllllllllllllllllllllllll
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`[11] Patent Number:
`[45] Date of Patent:
`
`5,470,411
`Nov. 28, 1995
`
`4,295,912 10/1981 Burns .................................... ..156/553
`5,048,178
`9/1991 Bindra et a1. ........................... .. 156/64
`
`FOREIGN PATENT DOCUMENTS
`
`0201952 11/1986
`0296511 12/1988
`0391790 10/1990
`608314 12/1978
`2031796 4/1980
`
`European Pat. Otf. .
`European Pat. Off. .
`European Pat. 01f. .
`Switzerland .
`United Kingdom .
`
`OTHER PUBLICATIONS
`
`[21] Appl. No.:
`
`' 107,710
`
`[22] PCT Filed:
`
`Feb. 18, 1992
`
`[86] PCT No.:
`
`PCT/FR92/00158
`
`§ 371 Date:
`
`Oct. 25, 1993
`
`§ 102(e) Date: Oct. 25, 1993
`[87] PCT Pub. No.: WO92/15118
`
`PCT Pub. Date: Sep. 3, 1992
`Foreign Application Priority Data
`
`[30]
`
`Feb. 19, 1991 [FR]
`
`France ................................. .. 91 01934
`
`[51] Int. Cl.6 .................................................... .. B32B 31/00
`[52] U.S. Cl. ............................ .. 156/64; 156/83; 156/282;
`156/351; 156/359; 156/543; 156/553
`[58] Field of Search ................................... .. 156/282, 351,
`156/359, 83, 64, 543, 553
`
`[56]
`
`References Cited
`
`U.S. PATENT DOCUMENTS
`
`Patent Abstracts of Japan, vol. 015114, Mar.
`1133004543, Jan. 1991.
`Patent Abstracts of Japan, vol. 014174, Apr. 1990;
`JP2026797, Jan. 1990.
`'
`Patent Abstracts of Japan, vol. 014401, Aug.
`JP2150101, Jun. 1990.
`
`1991;
`
`1990;
`
`Primary Examiner-John J. Gallagher
`Attorney, Agent, or Firm—Nil1es & Nilles
`
`[57]
`
`ABSTRACT
`
`The method consists in pressure bonding a ?rst strip to a
`second strip through a bonding press, marking each of the
`strips with the pattern pitches and juxtaposing the pattern
`pitch markings of each strip at the time of the bonding by
`extension of at least one strip with respect to another and by
`differential heating of each of the opposing strips to cause a
`relative shift, by expansion, of the two strips with respect to
`each other.
`
`3,458,382 7/1969 Buck ..................................... .. 156/543
`
`22 Claims, 4 Drawing Sheem
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`CONTROLLER
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`(AX,AY)
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`IMAGE
`ANALYZER
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`1
`METHOD FOR CONTINUOUS ASSEIVIBLY
`OF PATTERNED STRIPS AND INTEGRATED
`CIRCUIT MICROMODULE OBTAINED BY
`SAID METHOD
`
`BACKGROUND OF THE INVENTION
`
`1. Field of the Invention
`The present invention relates to a method for the continu
`ous assembly of patterned strips.
`It can be applied notably to the making of rnicromodules
`in integrated circuit form that go into the production of the
`portable fiat cards known as “chip cards”. In these cards, the
`micromodules are formed by a set of elements comprising:
`a chip in integrated circuit form, metal contacts used for the
`connection of the micromodule with external devices, link
`ing wires to link the chip to the metal contacts and a
`protective coat formed by a resin covering the chip, the
`linking wires and, partially, the metal contacts.
`2. Discussion of the Related Art
`To manufacture a micromodule and then incorporate it
`into a card, a ?rst known method consists in mounting the
`chip on a metal strip that has been pre-slotted in the form of
`a conductor grid, soldering the chip to a zone of this grid
`where it is connected by wires soldered to other zones of the
`grid, coating the chip and the wires with a drop of protective
`resin of the epoxy or silicone type in leaving the conductors
`of the grid partially bared, cutting up the metal strip into
`individual rnicromodules, each comprising a coated chip and
`bared external contacts and then bonding the micromodule
`to a surface cavity of a card made of plastic material in such
`a way that grid portions not coated with resin are ?ush with
`the surface of the card and constitute the external connector
`of the card.
`According to a second method which is also known, the
`initial pre-cut metal strip is replaced with a metallized
`dielectric strip etched with a connection pattern to be
`determined. The dielectrical strip, in this case, forms the
`main support of the chip. The connections have a very small
`thickness and are obtained by the pre‘deposition of a metal
`layer on the photo-etching plastic strip of this metal layer.
`The chip is connected by soldered wires to zones of the
`metallized layer.
`These methods have a certain number of drawbacks. In
`the case of the use of a pre-cut metal strip, the encapsulation
`resin of the micromodule adheres poorly to the conductors
`of the grid, all the more so as, in practice, the resin is on only
`one side of the strip, the other side being reserved to leave
`the conductors accessible to act as connectors. The result
`thereof is a problem of reliability that is di?icult to resolve,
`caused chie?y by the passage of moisture between the resin
`and the conductors.
`In the case of the use of. a metallized and photo-etched
`dielectric strip, the strip musk necessarily be made of a
`su?'rciently rigid material, and must stand up well to tem
`perature so as not to get warped when the temperature rises,
`which makes it necessary for the de?nition of the conduction
`pattern to be executed only by photo-etching on the dielec
`tric strip and makes this second method far costlier than a
`mechanical cutting-out operation for example.
`A third method is known through the European patent
`application published under N0. 0 296 511 and ?led under
`N0. 88 1097430 on 18th Jun. 1988.
`This patent application relates to a method for the manu
`facture of a ribbon designed to provide modules to equip
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`electronic cards also called “smart cards”. However, the
`approach proposed in this patent application is not satisfac
`tory.
`Indeed, this method entails taking a metal strip with a
`thickness that is typically equal to 75 micrometers but may
`vary between 50 micrometers and 150 micrometers. This
`strip is provided with perforations enabling it to be carried
`along and apertures obtained by stamping that demarcate the
`arrays of conductors of the circuits. A set of l25-microme
`ter-thick insulating foils having, on one face, a thermoplastic
`or therrnosetting material for hot bonding, is also‘ taken. The
`foils have a set of holes with an arrangement that corre
`sponds to the location of the connections and a central hole
`for the location of the circuit.
`The foils are bonded to the metal strip by heating. The
`heating prompts a certain shrinkage of the insulator material
`which makes it di?icult to use bigger foils, especially in the
`longitudinal direction. With cold bonding, the problem
`would not arise. By contrast, the adhesion to the metal is
`poor.
`Furthermore, it is imperatively necessary to make a per
`foration in each insulator foil at the position reserved for the
`circuit in order to house the circuit therein and thus keep
`within the requisite tolerances as regards thickness for the
`manufacture of the chip cards.
`Reference could also be made, as part of the prior art, to
`the document GB 2031796 A which describes a device for
`the assembling of an adhesive insulator strip to a conductive
`strip. In the device described, the adjusting of the tension is
`done only on the insulator strip by modifying the rotational
`speed of the wheels between which this strip passes. A
`device such as this does not enable the use of very thin 30
`to 50 um insulator strips as is made possible by the inven
`tion.
`
`OBJECTS AND SUMMARY OF THE
`INVENTION
`
`The present invention makes it possible to overcome these
`problems.
`Its object is a method for the continuous assembly of
`patterned strips. Apart from the advantage of continuous
`manufacture, the method also enables the use of a strip of
`insulator material with a far smaller thickness than is com
`monly used as an insulator thickness. This means that the
`manufacturer can be allowed the choice, as a function for
`example of the use that will be made, of placing the circuit
`either on the insulator strip or on the metal strip. Indeed,
`according to the invention, the dielectric strip may have a
`very small thickness of the order of 30 to 50 micrometers
`instead of 100 to 200 micrometers.
`The bonding of an integrated circuit chip may conse
`quently take place between the thin dielectric strip, the
`formation of the electrical connections to the chip then
`taking place through the slots of the dielectric strip. In any
`case, the total thickness of the micromodule is thus consid
`erably reduced by a decisive ratio which gives the possibility
`of manufacturing very ?at chip cards.
`Should the chip be bonded to the dielectric strip instead of
`being bonded to the metal surface, there is an additional
`safety factor, for the thin dielectric placed under the chip can
`then play a role of a plastic buffer preventing possible
`deterioration. Furthermore, the method according to the
`invention can do away with cases of incompatibility which
`have been encountered by the applicant during the bonding
`of the dielectric strip to the metal grid which should take
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`place at a temperature close to 200° C. and should prompt
`a differential expansion between the two materials, causing
`imprecision in the juxtaposition of the patterns of the
`dielectric strip above those of the metal grid. The method
`according to the invention makes it possible to resolve the
`problem of the relative conservation of the dimensions of the
`patterns in the longitudinal and transversal directions of the
`strips and their respective positioning when these strips are
`engaged between pinch rollers of bonding machines. A
`beginning of an approach to this problem may consist, for
`10
`example, in planning the overlapping pitch of the patterns as
`a function either of the expected bonding temperature or of
`the elasticity of the strips, or by stretching, for example, one
`of the two strips. However, the adjustment of the overlap
`ping pitch values as a function of the bonding temperature
`lacks ?exibility for the overlapping pitch of the strips should
`then be modi?ed whenever the bonding temperature or the
`nature of the materials constituting the strips is modi?ed, the
`stretching of the strips being valid only for low temperatures
`and expansion differences.
`Thus the proposed method for the continuous assembly of
`patterned strips consists in pressure bonding a ?rst strip to a
`second strip through a bonding press, marking each strip
`with the pattern pitch and juxtaposing the pattern pitch
`markings of each strip at the time of the bonding by
`extension of at least one strip with respect to another, and/or
`by di?erential heating of each of the opposing strips to cause
`a relative shift, through expansion, of the two strips with
`respect to each other.
`An object of the invention is also an integrated circuit
`micromodule comprising a pre-slotted metal grid, a perfo
`rated dielectric strip with a thickness of less than 70
`micrometers, a chip bonded either to this dielectric strip or
`to the metal strip through a perforation of the dielectric strip
`and connected to the metal strip through other perforations
`of the dielectric strip.
`An object of the present invention is also a device for the
`continuous assembly of patterned strips, one of which is a
`pre-slotted metal strip and the other is a pre-perforated
`insulator strip, comprising grip feeding means comprising a
`?rst strip unwinder on which there is mounted the metal strip
`wound on itself with an interposed strip preventing the
`imbrication of the patterns, a second strip unwinder on
`which the insulator strip is mounted, said strip being wound
`on itself with an interposed strip, characterized in that it
`comprises means for the marking, on each of the strips, of
`the pattern pitches, means for adjusting the tension of either
`of the strips and means for adjusting this tension that enables
`the prompting of a differential heating of each of the
`opposing strips, to obtain a relative shift, by expansion, of
`the two strips with respect to each other.
`An object of the present invention is also an integrated
`circuit module in which the dielectric strip covering the grid
`constitutes the dielectric of an electromagnetic transmission
`or reception antenna, the pre-slotted grid of which consti
`tutes an active part.
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`BRIEF DESCRIPTION OF THE DRAWING
`
`Other characteristics and advantages of the present inven
`tion shall appear from the following description, made with
`reference to the appended drawings, of which:
`FIG. 1 is a top view of a pre-slotted metal strip according
`to the invention;
`FIG. 2 is a top view of a perforated dielectric strip
`according to the invention, designed to be bonded to the
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`metal strip of FIG. 1;
`FIG. 3 is a view showing the juxtaposition of the two
`strips being bonded;
`FIG. 4 shows a device for the implementation of the
`method according to the invention;
`FIG. 5 represents a press used for the implementation of
`the method according to the invention;
`FIG. 6 shows the micromodule manufactured according
`to the invention, at an intermediate stage of manufacture;
`FIG. 7 shows a micromodule according to the invention,
`at a ?nal stage of manufacture;
`FIG. 8 represents a micromodule constituting a transmis
`sion/reception antenna;
`FIG. 9 represents a micromodule constituting an identi
`?cation label.
`
`DETAILED DESCRIPTION OF THE
`PREFERRED EMBODIMENT
`
`The pre-slotted metal strip 10 which is shown in FIG. 1
`is formed by a strip of copper or tinned copper with a
`thickness of about 35 to 70 micrometers. Its width is de?ned
`to correspond to the ?nal connection width to be obtained,
`and may be of the order of one centimeter to some centi
`meters as the case may be. It is slotted with a repetitive
`pattern 102 which, as the case may be, is done by stamping
`to de?ne the separate contacts 3 used as connection pins
`between the interior and the exterior of the micromodule to
`be assembled on the strip.
`In the representation shown in FIG. 1, which is given by
`way of an example, the pattern 102 is the one that enables
`the connection of a micromodule for ?at chip cards, the
`contacts shown being eight in number. The eight separate
`contacts 3 can be seen inside a closed line 4. These contacts
`are separated by cutting lines 5 that cut out the patterns 102.
`Outside the line 4, the contacts are joined to ensure the
`continuity of the strip from one micromodule to another.
`The strip 10 comprises regular perforations 6 distributed
`along the longitudinal edges of the strip on one or both of its
`sides. These perforations are used to carry the strip along by
`a toothed wheel system.
`The slotted metal strip forms‘the main support of the chips
`constituting the core of the micromodules. This strip is
`covered with a dielectric strip of the type shown in FIG. 2, '
`comprising pre-cut perforations (Pl-P8) designed to come
`before conductive zones 3 of the conductive pattern cut out
`of the metal strip 10. An indexing hole (1) serves as a
`reference mark and enables the precise positioning of the
`perforations (Pl-P8) facing the conductive zones 3 during
`the operation for the hot bonding of the two strips to each
`other. As clearly illustrated in FIG. 1, a corresponding
`reference mark is foraged in the metal strip 10 in the form
`of an indexing hole (I).
`As indicated in FIG. 3, the indexing hole (I) of each strip
`is located, when the bonding operation is terminated, at the
`intersection of the two bonding axes, respectively the hori
`zontal axis X and the vertical axis Y formed by the cutting
`lines 5. This positioning is done by the strip assembling
`device shown in FIG. 4.
`This device comprises a press 7 comprising two plates or,
`possibly, two juxtaposed rollers 8 and 9, between which
`there move patterned strips 10 and 11 that have to be
`assembled by bonding. In FIG. 4, the upper plate or roller 8
`is heated up to a bonding temperature of about 200° C. by
`an electrical resistor R supplied by an external electrical
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`current supply device (not shown). The lower plate 9 is
`cooled by a water circulation circuit 12 going through a heat
`pump type of temperature exchanger 13 or any other equiva
`lent device activated by a pump 14. The strips 10 and 11,
`once bonded, are carried along in a translation motion
`between the two plates or rollers 8 and 9 by a sprocket wheel
`15, the teeth of which engage in the perforations 6 of the
`support strip or cross-motion clamp system. The sprocket
`wheel 15 is moved by a motor 16. The strips 10 and 11 are
`paid out respectively from two loading rollers 17 and 18.
`Indeed, in order to obtain a continuous assembly of the strips
`10 and 11, these strips are each mounted on an unwinder and
`moved by a motor (not shown).
`The strip 10 is mounted on the roller 17 while the strip 11
`is mounted on the roller 18. The strip 10 is wound on itself
`with an interposed strip 41 that falls as and when the strip 10
`unwinds. This interposed strip 41 prevents the patterns from
`getting imbricated with one another. The strip 11 is also
`wound on itself. An intercalary strip 51 may be planned too,
`to prevent problems during the unwinding of the strip 11.
`The traction of the supporting strip 10 is adjusted by a
`presser wheel 19 on a beam 20 of the supporting strip 10.
`The beam 20 then retains the strip 10 by friction and
`procures the tension of this strip. The tension of the strip to
`be bonded 11 is adjusted by two pinch rollers 21 and 22 with
`calibrated friction. A controller 23 provides, ?rstly, for the
`rotational control of the motor 16 and the pump 14 and,
`secondly, for that of the presser wheel 19. The controller 23
`receives information elements coming, ?rstly, from a camera
`24 by means of an image analyzer 25 and, secondly, a
`temperature sensor 26 connected to the ?uid circulation
`circuit 12, as well as a device 27 formed by a tensiometer or
`any other equivalent device to measure the tension of the
`supporting strip 10. Thus when the two strips 10 and 11
`driven by the traction of the motor 16 move past under the
`rollers or between the two plates 8 and 9, the image analyzer
`25 can permanently provide information on the offset Delta
`X and Delta Y of the reference hole or indexing hole (I) with
`respect to the reference axes X and Y of each pattern. The
`value of this arrangement is that, through the controller 23,
`it enables action jointly or separately on the pressure exerted
`on the strip 10 or the strip 11 respectively, by the presser
`wheel 19 in order to adjust the tension of the strip 10 or the
`strip 11 by the pinch rollers 21 and 22 and by the adjusting
`of the temperatures of the two plates or pinch rollers 8 and
`9 in order to adjust, by extension or expansion, the position
`of one strip with respect to the other one to obtain the
`coinciding of the indexing holes of the two strips by can
`celling the offsets Delta X and Delta Y of the reference hole
`with respect to the reference axes X and Y. It must be noted,
`however, that an adjusting of the pitch by the simple
`extension of one of the two strips in relation to the other is
`valid only for the small offsets Delta X and/or Delta Y of the
`values of the pitch, and that big o?‘sets can be e?iciently
`compensated for only by an adjustment of the relative
`temperatures of the plates or rollers 8 and 9 with respect to
`each other. In practice, when an offset Delta X exceeds a
`predetermined threshold, the compensation for this offset is
`achieved by the controller 23 acting on the cooling of the
`plate 9. In the case of small o?sets, the compensation is
`achieved by acting on the pinch rollers 19 or 21, 22.
`However, for the system to work efficiently, it is preferable
`to apply the strip that has the highest expansion coefficient
`to the plate or roller 9 which is cooled, the other strip 11
`being applied to the plate or roller 8 that is heated. Thus, for
`example, for a bonding of a copper roll which has an
`expansion coefficient of l7XlO_6/°C. on a roll of a plastic
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`material, commercially available under the registered mark
`“Kapton”, which has an expansion coe?icient of 20><l0_6/
`°C., the Kapton should be applied to the plate or roller 9 and
`the copper to the plate or pinch roller 8.
`During the bonding operation, it should naturally be seen
`to it, when the plates/rollers 8 and 9 come under pressure,
`that these elements 8 and 9 move properly solely in the
`direction Z normal to the plane (X, Y) of the two strips. The
`problem can be resolved easily by using either column
`presses or presses with distribution springs. However, to
`avoid having the positions, between the axes, that evolve
`with the temperatures, it is desirable, in the case of the
`column presses, to use steels with a low expansion coe?i~
`cient by using, for example, steel that is commercially
`distributed under the known registered mark Invar for
`example.
`The approach using a rod-type press, a diagram of the
`embodiment of which is shown in FIG. 5, has the advantage
`of being easy to make and of providing homogeneous
`pressure between the two plates. As can be seen in FIG. 5,
`where the elements homologous to those of FIG. 4 are
`shown with the same references, a press comprises a lower
`plate 9 formed by a steel board 28 mounted on an insulating
`board -29 and an upper plate 8 formed by a steel board 30
`comprising a hollow insulating cap 31 enclosing the head 32
`of a rod 33. The steel board 28, on its surface facing the steel
`board 30, has distribution springs 34 which enable the rod
`head 32, the steel board 30 and the spring 34 to be all in
`contact together before the pressure of the two boards 28 and
`30 is exerted on the two strips 10 and 11, thus preventing any
`motion in the directions X and Y during the clamping of the
`two boards.
`Once the bonding is done, it can be further homogenized,
`possibly by a second press (not shown), which then has the
`same temperatures on both plates, or by two rollers similar
`to those already used in the prior art.
`Naturally, the method that has just been described can
`equally well be applied with the same efficiency for the
`indexed assembly of any material with identical or multiple
`pitch patterns. The method can also be applied to the
`bonding of any number N of strips by the interposing of N
`pre-bonding presses before the homogenization station. The
`usefulness then is that it enables the making of multilayer
`?lms continuously.
`Thus the method according to the invention enables the
`manufacture of integrated circuit rnicromodules, this manu—
`facture comprising the formation of a pre~slotted metal strip
`comprising notably regular perforations enabling the strip to
`be carried along by toothed wheel (as with the forward feed
`of a cinema film), the formation of a very thin perforated
`dielectric strip and then the bonding of the two strips to each
`other, the bonding of an integrated circuit chip to the thin
`dielectric strip and the formation of electrical connections
`between the chip and the metal strip through the slots of the
`dielectric strip. In principle, the electrical strip will be
`narrower than the metal strip: it will include no periodic
`lateral slots enabling it to be carried along by toothed wheel
`and furthermore, it will generally be too thin to be carried
`along by a toothed wheel. During the bonding of the
`dielectric strip to the metal strip, the slots enabling the metal
`strip to be carried along will not be covered by the dielectric
`strip owing to the smaller width of this strip.
`The other manufacturing operations may be standard
`ones, for example: the deposition of a drop of resin to coat
`the chip and the connections with the chip, on the dielectric
`strip side but not on the metal strip side, and possibly the
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`levelling down of the drop to a determined height; the
`separation of the micromodule from the rest of the strip. The
`micromodule is then ready to be inserted into a cavity of a
`plastic card.
`It is furthermore observed that, by this method, it is no
`longer the dielectric strip that is used to carry the unit along
`during the assembly line manufacture of micromodules out
`of a continuous strip, as might have been the case in the prior
`art technique when a dielectric strip was provided for. The
`thickness of the dielectric strip is far smaller than in the prior
`art, 30 to 50 micrometers instead of 100 to 200 micrometers
`for example. This is very important, for the total thickness
`of the micromodule is a decisive factor for the possibility of
`making very ?at chip cards.
`Furthermore, in view of this very small thickness, the chip
`may be bonded to the dielectric strip or to the metal strip.
`Cases where it is not necessary to provide for a rear face
`contact are indeed frequent in CMOS technology. When
`mechanical stresses are exerted on the card, the thin dielec
`tric placed beneath the card plays the role of an elastic buffer
`which, in certain cases, prevents the chip from deterioration.
`During the manufacture, the small thickness of the dielec
`tric strip facilitates a very ef?cient bonding of the two strips
`to each other, without any risk of their getting separated
`during the subsequent treatment.
`Finally, another advantage of the invention is that the
`bonding of the chip to the dielectric makes it possible to
`provide for only one micromodule manufacturing line,
`whatever the dimension of the chip to be encapsulated, this
`being achieved with a single model of pre-slotted metal
`strip, the sole condition being that there should be provided
`a modi?able or detachable punching tool for the formation
`of the slots in the electrical strip; indeed, the chip is insulated
`from the metal grid, and only the location of the perforations
`in the dielectric de?nes the position of the connections
`between the chip and the grid. For a larger-sized chip, the
`perforations will be placed at a greater distance from the
`center of the chip. For a smaller chip, the perforations will
`be brought closer to the center. It is naturally sufficient for
`the perforations to remain above the appropriate metal
`zones, but these zones may be fairly wide in the case of
`micromodules with a small number of external contacts (6 or
`8 for example).
`The invention also relates to a micromodule comprising a
`slotted metal grid bonded to the very thin perforated dielec
`tric strip (thickness preferably smaller than 50 micrometers,
`more generally between 30 and 70 micrometers), with a chip
`bonded either to ,the metal strip or to the dielectric strip and
`connected to the metal strip through the perforations of the
`dielectric strip.
`FIG. 6 shows the composite strip bearing a chip 100 at this
`stage of manufacture. The references are the same as in the
`foregoing ?gures.
`The chip 100 is then coated with a protective insulator
`101, preferably an epoxy resin or a silicone resin that can be
`deposited in drops above the chip (FIG. 7).
`It will be noted that, contrary to what happens in the
`technique using a slotted metal strip without dielectric, the
`resin cannot ?ow between the conductors 103, i.e. in the
`slots 102 of the metal strip since, in principle, all these slots
`102 are covered with the dielectric strip, at least in the part
`that will constitute the micromodule after the slotting of the
`strip.
`'
`The mechanical stresses on the chip are particularly low
`during and after the manufacture owing to the interposition,
`between the metal and the chip, of a small thickness of
`
`10
`
`25
`
`35
`
`45
`
`50
`
`55
`
`60
`
`65
`
`8
`polyinride which behaves like a buffer of plastic material.
`This is important when the micromodule is incorporated into
`a ?at chip card for these cards are subject to very substantial
`twisting and bending stresses.
`Given that it is possible to be satis?ed with a very small
`thickness of dielectric, the height of the micromodule
`remains limited to an acceptable value despite the fact that
`the chip lies on the dielectric. By way of an indication, the
`chip may have a thickness of about 250 micrometers and the
`strips 10 and 11 a thickness of about 50 micrometers each.
`The encapsulation resin adheres to a dielectric surface,
`which is better than if it were to adhere to a metal surface.
`There is no risk of any penetration of moisture up to the chip
`which is surrounded with resin wherever it does not touch
`the dielectric strip.
`When the micromodule is ?nished (FIG. 7), if necessary,
`after the levelling down of the resin to a maximum desired
`height, it is separated from the rest of the strip by being cut
`out mechanically along the line 4 of FIGS. 1 and 2. If it is
`a micromodule for chip cards whose connector is constituted
`by the accessible face of the conductors 103, the micromod
`ule is placed in a cavity of the chip card, the face that bears
`the chip being pointed towards the bottom of the cavity and
`the conductors remaining accessible at the upper part.
`In one improvement of the invention (cf. FIG. 8), which
`is especially promising in the case of chip cards working in
`microwave applications and designed to receive and/or send
`an electromagnetic radiation, it is possible to provide for an
`arrangement where the dielectric strip 11 constitutes the
`dielectric of a radiating antenna, of which the slotted grid 10
`constitutes an active part. The antenna 90 is of the microstrip
`type constituted, for example, by conductors cut out in the
`metal strip and acting as antennas instead of as connectors.
`An electrical ground plane 25 can then be provided for on
`the other side of the dielectric. This ground plane can be
`formed either by means of a second metal strip 10 mechani
`cally cut out and bonded to the upper face of the dielectric
`strip 11 before the positioning of the chips or by means of
`a photo-etched metallization on the upper face of the dielec
`tric. Conversely, it can be provided for the ground plane to
`be beneath (formed in the metal strip 10) and the microstrip
`antenna above (formed in the metallization of a metallized
`dielectric strip 11, or formed in a second metal strip bonded
`to the side of the chip).
`According to the alternative embodiment, the micromod
`ule may constitute an identi?cation label. To this end, the
`grid 10 forms an inductor 90. The chip 1004 can be placed
`in a metal zone and can be connected to both ends of the
`inductor 90. Advantageously, a low-cost dielectric will be
`used, for example cardboard. A micromodule such as this is
`shown in FIG. 9 and constitutes a low-cost identi?cation
`label.
`We claim:
`1. Method for the continuous assembly of patterned strips,
`one of which is a pre-slotted metal strip and the other a
`pre-perforated insulator strip, comprising providing each of
`the strips with reference marks, continuously unwinding the
`strips from respective feeder rollers, continuously transport
`ing the strips through a bonding press under tension, sensing
`the locations of said reference marks, pressure bonding the
`?rst strip to the second strip through the bonding press, and,
`in response to said sensing step, juxtaposing the reference
`marks of each strip at the time of the bonding by at least one
`of (l) varying the tension applied to at least one of said strips
`so as to extend one strip with respect to the other, and (2)
`differentially heating each of the opposing strips to cause a
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`9/10
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`DOJ EX. 1018
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`

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`5,470,411
`
`9
`relative shift, by expansion, of the two strips with respect to
`each other.
`2. Method according to claim 1, wherein the bonding is
`performed using a plate press comprising a ?rst plate that is
`electrically heated and a second pl