United States Patent [191
`Moskowitz et al.
`
`[54] RADIO FREQUENCY CIRCUIT AND
`MEMORY IN THIN FLEXIBLE PACKAGE
`
`[75] Inventors: Paul A. Moskowitz, Yorktown Heights; Michael J. Brady, Brewster; Paul W.
`
`Coteus, Yorktown Heights, all of NY.
`
`[73] Assignee: International Business Machines
`C(IYPOPHWL Armonk’ N-Y-
`
`[21] Appl‘ No": 303,977
`[22] Filed;
`Sep_ 9, 1994
`
`6
`[51] Int. Cl. ..................................................... .. H04Q 1/02
`[52] US. Cl. ............................ .. 340/572; 29/825; 29/829;
`[58] F m f 22/832; 340/8253; 340/82323; 330438225551
`
`llllllllllllllllllllllll|l|llllllllllllllllllll||l|llllllllllllllllllllllll
`59,528,222
`Jun. 18, 1996
`
`US005528222A
`[11] Patent Number:
`
`[45] Date of Patent: >
`
`0595549 5/1994 European Pat. 01f. .
`4319373 12/1993 Germany -
`2173888 9/1990 Japan .
`'
`1(5);
`9411846 5,1994 WIPO '
`
`OTHER PUBLICATIONS
`Patent Abstracts ofJapan, vol. 13, No. 560 (M—906) 13 Dec.
`1989 & JP, A, 01 234 296 (NEC Corp.) 19 Sep. 1989.
`International Standard 7810, “Identi?cation cards-Physical
`characteristics” First Edition-l 98542-15.
`R. R. Tumalla et al, “Microelectronics Packaging Hand
`book”, 1989, pp 68’ 76, 1154
`
`Primary Examiner—Glen Swann
`
`>
`
`1e O
`
`
`
`
`
`
`
`, are ............................. .. 340/8253, 825.54; 29/836, 829, 825 . ,
`
`
`
`
`
`Art "my gen 0' m" on“ we 0 , A I, _L ' P
`
`
`
`
`
`
`
`[56]
`
`References Cited
`UIS_ PATENT DOCUMENTS
`
`3,934,122
`4,009,375
`4,674,175
`
`5’014’040
`,
`,
`5,204,663
`
`1/1976 Riccitelli .......................... .. IMO/825.34
`2/1977 White 6131-
`------ -- 364/436
`6/1987 Starnp?1 ............ ..
`437/209
`gamalliawa et a1‘
`5,1991 wmo """"""" "
`eaver et a1.
`4/1993 Lee . . . . . . . . . .
`
`340/572
`. . . .. 340/8253
`
`ABSTRACT
`[57]
`A novel thin and ?exible radio frequency (RF) tag has_a
`sennconductor circuit with logic, memory, and a radio
`frequency circuits, connected to an antenna with all inter
`connections placed on a single plane of wiring without
`crossovers_ The elements of the package (substrate, antenna,
`and laminated covers) are ?exible. The elements of the
`package are all thin. The tag is thin and ?exible, enabling a
`.
`.
`.
`.
`.
`_
`.
`“mque range of apphcauons mcludmg- RF ID taggmg of
`
`. . . . . . .. 340/572
`5,257,011 10/1993 Beigel . . . . .
`5,396,218
`3/1995 Olah ...................................... .. 340/572
`
`Credit caIdS, Passports, admission tickets, and Postage
`Stalnps
`
`FOREIGN PATENT DOCUMENTS
`
`0481776 4/1992 European Pat. O?‘. .
`
`29 Claims, 10 Drawing Sheets
`
`\
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`1/15
`
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`
`

`
`US. Patent
`
`Jun. 18, 1996
`
`Sheet 1 of 10
`
`5,528,222
`
`FIG. IA
`PRIOR ART
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`2/15
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`U.S. Patent
`
`Jun. 18,1996
`
`Sheet 2 of 10
`
`5,528,222
`
`200
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`3/15
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`US. Patent
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`Jun. 18, 1996
`
`Sheet 3 of 10
`
`5,528,222 ‘
`
`FIG.3
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`US. Patent
`
`Jun. 18, 1996
`
`Sheet 4 of 10
`
`5,528,222
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`FIG.4
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`US. Patent
`
`Jun. 18, 1996 '
`
`Sheet 5 of 10
`
`5,528,222
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`
`6/15
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`US. Patent
`
`Jun. 18, 1996
`
`Sheet 6 0f 10
`
`5,528,222
`
`FIG.7B
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`PRIOR ART
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`US. Patent
`
`Jun. 18, 1996
`
`Sheet 7 of 10
`
`5,528,222
`
`FIG.7D
`PRIOR ART
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`U.S. Patent
`
`Jun. 18, 1995
`
`Sheet 8 of 10
`
`5,528,222
`
`E‘¢'\;-\J-\f\/-\/‘L’-\z‘.f\f\j
`
`PASSPORT
`
`U N ITED STATES
`
`9/15
`
`DOJ EX. 1003
`
`

`
`US. Patent
`
`Jun. 18, 1996
`Sheet 9 of 10
`FIG.IO
`
`5,528,222
`
`I ADMISSION
`TICKET
`
`$ 5
`.00
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`- ‘*1
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`I020
`
`EXPIRES 12/31/95
`
`CD w/uzo
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`10/15
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`US. Patent
`
`Jun. 18, 1996
`
`Sheet 10 0f 10
`
`5,528,222
`
`FIG. I2
`
`’
`[I |—
`Izzo/ L 1'
`__._I
`
`Credi’r Card
`
`x\—I2I0
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`/\/\/\//J
`1234 5678 9IOI
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`JOHN A. DOE (I)
`\ EXPIRES 12/31/95
`1
`
`FIG. I3
`
`.’ NEW YORK STATE fl “
`MISIO
`1995 DRIVER LICENSE
`QM:
`DOE, JOHN A.
`COMMISSIONER
`+234 SOMEPLACE
`3 ANYWHERE,N.Y. moo .
`C5 3
`ABCDEF'------ _____
`LI
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`11/15
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`
`5,528,222
`
`1
`RADIO FREQUENCY CIRCUIT AND
`MEMORY IN THIN FLEXIBLE PACKAGE
`
`FIELD OF THE INVENTION
`
`This invention relates to a radio frequency circuit and
`memory in a thin ?exible package. More speci?cally, the
`invention relates to a thin ?exible radio frequency circuit
`used as a radio frequency tag.
`
`BACKGROUND OF THE INVENTION
`
`2
`these devices can be turned off once but cannot be reacti
`vated.
`FIG. 1A shows one prior art structure of a radio frequency
`tag 105. The tag 105 has a chip 110 mounted on a substrate
`115. The chip 110 has contacts 120 that are connected to
`circuitry on the substrate 115 by wire bonds 125. An
`encapsulation material 130 covers the chip for environmen
`tal protection. The thickness of this tag 105 is determined by
`the combined thicknesses of the chip components. Typically,
`substrates in these tags are at least 10 mils, 0.25 mm, in
`thickness, the chip 110 along with the high loop 122 of the ,
`bond vary from 20 to 40 mils, 0.5 to 1 mm, in thickness and
`the encapsulation 130 is about 10 mils, 0.25 mm in thick
`ness. As a result, tags 105 of this structure vary from a
`minimum of 40 to 60 mils, l to 1.5 mm, in thickness. This
`structure is too thick for many potential tag applications.
`FIG. 1B shows another prior art structure 150 showing a
`chip 110 with the chip contacts 120 connected to circuitry
`contacts 155 with conducting adhesive 160. The substrate
`165 of this structure 150 is typically made as a FR4/printed
`circuit (thickness 40 to 60 mils, l to 1.5 mm) or ?exible
`substrate (10 mils,0.25 mm). The chip 110 and adhesive 160
`add another 20 to 40 mils, 0.5 to 1 mm, to the thickness and
`the encapsulation 130 adds still another 10 to 20, 0.25 to 0.5
`mm mils in structure 150 thickness. This structure therefore
`can vary in thickness from 80 to 130 mils, 2 to 3.5 mm,
`making it thicker than the structure in FIG. 1A.
`Other thick structures are known in the art. These include
`quad ?at pak (QFP) and/or small outline pak (SOP) as
`components. Structures made with these components are at
`least 1 mm thick and usually 2 to 3 mm thick.
`
`PROBLEMS WITH THE PRIOR ART
`
`Prior art teaches that there is a long felt need to manu
`facture thin RF ID tags on ?exible substrates. However,
`while the goal of a thin ?exible tag is desired, the prior art
`has failed to reach the goal. One prior art reference discloses
`a tag that is 1.5 to 2.0 mm thick. This tag thickness limits the
`applications of this tag. For example, it is far thicker than the
`International Organization for Standardization (ISO) stan
`dard credit card thickness of 0.76 mm and therefore could
`not be used in a credit card to be inserted into a credit card
`reader.
`The prior art has failed to produce a thin tag because: care
`is not been taken to make each of the elements thin; elements
`are stacked one upon the next; and the antenna and con
`necting conductors require more than one plane of electrical
`wiring, ie. the designs use cross-overs for completing inter
`connections. As elements are stacked and layers are added
`the package grows thicker and ?exibility is lost.
`Another prior art reference discloses a package with a
`total thickness of 0.8 mm. This is still greater than the ISO
`standard credit card thickness of 0.76 mm. Furthermore,
`while thin elements are disclosed, no care is taken to use
`?exible materials throughout. The components are mounted
`on a hard circuit card and encapsulated in plastic. (Hard
`means can not be torn easily by hand.) The result a is rigid
`package. The prior art has not shown the use of thin ?exible
`laminate covering materials for the packages. The results are
`that the packages are thick, and in?exible.
`
`OBJECTS OF THE INVENTION
`
`An object of this invention is an improved thin radio
`frequency tagging apparatus.
`
`Radio Frequency Identi?cation (RF ID) is just one of
`many identi?cation technologies for identifying objects. The
`heart of the RF ID system lies in an information carrying tag.
`The tag functions in response to a coded RF signal received
`from a base station. Typically, the tag re?ects the incident RF
`carrier back to the base station. Information is transferred as
`the re?ected signal is modulated by the tag according to its
`programmed information protocol.
`The tag consists of a semiconductor chip having RF
`circuits, logic, and memory. The tag also has an antenna,
`often a collection of discrete components, capacitors and
`diodes, for example, a battery in the case of active tags, a
`substrate for mounting the components, interconnections
`between components, and a means of physical enclosure.
`One variety of tag, passive tags, has no battery. They derive
`their energy from the RF signal used to interrogate the tag.
`In general, RF ID tags are manufactured by mounting the
`individual elements to a circuit card. This is done by using
`either short wire bond connections or soldered connections
`between the board and the circuit elements: chip, capacitors,
`diodes, antenna. The circuit card may be of epoxy-?berglass
`composition or ceramic. The antennas are generally loops of
`wire soldered to the circuit card or consist of metal etched
`or plated on a circuit card. The whole assembly may be
`enclosed in a plastic box or molded into a three dimensional
`plastic package.
`While the application of RF ID technology is not as
`widespread as other ID technologies, bar code for example,
`RF ID is on its way to becoming a pervasive technology in
`some areas, notably vehicle identi?cation.
`Growth in RF ID has been inhibited by the high cost of
`tags, the bulkiness of most of the tags, and problems of tag
`sensitivity and range. A typical tag costs in the $5 to $10
`range.
`Companies have focused on niche applications. Some
`prior art is used to identify railway boxcars. These tags tend
`to be quite large and are made of discrete components on
`circuit boards mounted in solid, non-?exible casings. RF
`tags are now used in the automatic toll industry, e.g. on
`thruway and bridge tolls. RF tags are being tested for uses
`as contactless fare cards for buses. Employee identi?cation
`badges and security badges have been produced. Animal
`identi?cation tags are also commercially available as are RF
`ID systems for tracking components in manufacturing pro
`cesses.
`Tags exist that have the-length and width of a standard
`credit card. However, these cards typically are over 2.5 mm
`thick and have a non-?exible casing. Tags also exist that
`have a credit card size length and width but with bumps
`where circuit is placed that causes them to be too thick to ?t
`in card reader machinery
`While some electronic article surveillance (EAS), e.g.
`antitheft devices, are thin (0.3 mm) they typically contain
`limited amounts, (i.e., only one bit) of information. Some of
`
`15
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`3
`An object of the invention is a ?exible radio frequency tag
`apparatus with a thin ?exible protective lamination.
`An object of the invention is a ?exible radio frequency tag
`apparatus that may ?t within the thickness limit of an ISO
`standard credit card, a passport cover, a postage stamp, an 5
`anti-theft device, or an admission ticket.
`
`SUMMARY OF THE INVENTION
`
`The present invention is a novel radio frequency (RF) tag
`that comprises a semiconductor circuit that has logic,
`memory, and radio frequency circuits. The semiconductor is
`mounted on a substrate and is capable of receiving a RF
`signal through an antenna that is electrically connected to
`the semiconductor through connections on the semiconduc
`tor. The present invention is a novel structure of a radio
`frequency tag design that is thin and ?exible. The tag has the
`antenna and all interconnections placed on a single plane of
`wiring without crossovers. The elements of the package are
`placed adjacent to one another, i.e., they are not stacked.
`Elements of the package, the substrate, antenna, and lami
`nated covers, are ?exible. The elements are all thin such that
`the total package thickness including covers does not exceed
`that of an ISO standard credit card. The resulting tag
`package, comprised of thin, ?exible components arranged
`and connected in a novel way, is also thin and ?exible.
`Accordingly, this enables a novel range of applications that
`include: RF ID tagging of credit cards, passports, admission
`tickets, and postage stamps.
`BRIEF DESCRIPTION OF THE DRAWINGS
`
`30
`
`FIG. 1, comprising FIGS. 1A and 1B, is a drawing
`showing the cross section view of two typical embodiments
`in the prior art.
`FIG. 2 is drawing showing a cross section of one preferred
`embodiment of the present thin RF ID tag.
`’
`FIG. 3 is drawing showing a cross section of one preferred
`embodiment of the present thin RF ID tag with an aperture
`in the substrate.
`FIG. 4 is a top view of the thin tag showing a dipole
`antenna.
`FIG. 5 is a top view of a thin tag having more than one
`folded dipole antennas.
`FIG. 6 is a top view of a thin tag having a battery included
`in the circuit.
`FIG. 7 comprises FIGS. 7A-7E which are cross sections
`of prior art chip bonds to substrates by means of thermo
`compression bonding (FIG. 7A), ultrasonic bonding (FIG.
`7B), C4 solder bonding (FIG. 7C), conducting adhesive
`bonding (FIG. 7D), and spot welding (FIG. 7E).
`FIG. 8 shows a thin tag used as a postage stamp.
`FIG. 8A shows a thin tag enclosed in a parcel membrane
`or in the wall of an envelope.
`FIG. 9 shows a thin tag placed in the cover of a passport 55
`using a resonant loop antenna.
`FIG. 10 shows a thin tag used on an admission ticket.
`FIG. 11 shows a thin tag used as an antitheft device.
`. FIG. 12 shows a thin tag placed inside a credit card.
`FIG. 13 shows a thin tag placed inside a license.
`
`60
`
`45
`
`DETAILED DESCRIPTION OF THE
`INVENTION
`
`FIG. 2 shows a side view of a novel RF ID tag 200. The 65
`chip 210 is located on a ?exible substrate 220. The chip 210
`with bumps 225 on contacts 222 is bonded to an antenna 230
`
`4
`contained on the substrate 220. The package is sealed by thin
`?exible laminations 270 consisting of a hot-melt adhesive
`250 such as EVA on the inside and an outer coating 260 of
`a tough polymeric material on the outside.
`The antenna is manufactured as an integral part of the
`substrate. It will consist of thin, typically 25 to 35 micron
`thick copper lines which have either been etched onto a
`copper/organic laminate or plated on the organic surface.
`The thinness of the copper maintains the ?exibility of the
`substrate. Typical materials used are polyester or polyirnide
`for the organic and electroplated or rolled annealed copper.
`The copper may be gold or tin plated to facilitate bonding.
`The chip is connected to the antenna lines by means of
`bumps on the chip, either plated gold bumps for thermo
`compression bonding or C4 solder bumps for solder bonding
`are preferred. The bumps 225 then become the connecting
`lines. Since they are only on the order of 25 microns or so
`they will not degrade electrical performance by introducing
`unwanted inductance into the circuit. The novel design has
`a single metal layer with no vias (between-plane connectors
`through a dielectric layer) in the ?exible continuous ?lm. By
`using only one level of metal to produce the antenna and
`interconnections, the package is kept thin. Further novelty of
`the invention includes arranging the components (chip and
`antenna and possibly a battery) in adjacent proximity to one
`another. This means that the components are close (i.e., not
`stacked). In a more preferred embodiment the closeness is
`insured because the chip 210 is bonded directly to the
`antenna 230 without the use of crossovers in the circuit. This
`is accomplished by using either a dipole, loop or folded
`dipole antenna that is resonant rather than using a multiloop
`antenna which requires cross-overs for connection. Thus all
`of the wiring is placed in a single plane. Keeping the antenna
`adjacent to the chip, avoiding cross-overs and stacking, also
`contributes to keeping the package thin.
`To maintain the thinness of the package, the chill is made
`to be 225 to 375 microns thick by thinning. In general,
`semiconductors are manufactured on thick wafers, up to 1
`mm thick. Thinning may be done by polishing or backgrind
`ing of the wafer after manufacture. All elements and bonds
`are very thin. The elements are preferably: the chip (and
`battery if used) are 10 to 12 mils (250 to 300 microns) thick
`or thinner; the bonding structures are 2 mils (50 um) or less;
`laminating materials 2 to 4 mils (50 to 125 um) per side; to
`produce total thickness preferably of about 20 mils (500 um)
`or less but in any case less than 30 mils (750 um). Bonding
`mechanisms do not add to thickness of the tag as would
`techniques like wirebonding.
`Although not required in one preferred embodiment, a
`unique ?exible covering material 270 may be laminated
`upon one or both sides of the package. In another preferred
`embodiment, the material consists of two layers (250, 260).
`A soft copolymer such as ethyl-vinyl-acetate is located on
`the inside 250 surface of the cover. Tough polyester is
`located on the outside 260 surface. This combination pro
`vides environmental protection while maintaining the ?ex
`ibility of the package. Typical thicknesses of the covers
`range from 50 to 125 microns. Alternately, a single layer of
`laminate such as polyethylene, polyester, mylar or polyim
`ide may be used for covering.
`FIG. 3 shows a side view of a unique RF ID tag 300. The
`chip 310 with contacts 322 and bumps 325 is bonded to
`antenna 330 thru window 315 in substrate 320. In a more
`preferred embodiment, encapsulant 340 is used to protect
`the chip 310, the bonds 325 on contacts 322, connected to
`‘antenna 330 located in window 315 between substrate 320
`from environmental exposure. In a still more preferred
`
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`5,528,222
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`5
`embodiment, the package is sealed by thin ?exible lamina
`tions 370 consisting of hot melt adhesive 350 such as EVA,
`phenolic butyral, or silicone adhesive on the inside and an
`outer coating 360 of a tough polymeric material (such as
`polyester, mylar, polyimide, and polyethylene) on the out
`side. In an alternative preferred embodiment, layer 370
`comprises a single layer of organic material.
`In order to further reduce the thickness of the package, the
`substrate is manufactured with a window allowing the
`insertion of the chip into the window. Thus, the thickness of
`the substrate is not added to the thickness of the chip. The
`window is produced in organic materials, polyimide or
`polyester by either etching or punching. In addition, the
`window may be used to allow the coating of the chip with
`a thin layer of encapsulation material. Hysol epoxy 4510 is
`one such material. The encapsulant does not add substan
`tially to the total package thickness, adding perhaps 50
`microns, but does provide additional environmental protec
`tion for the chip. Opaque materials in the encapsulant protect
`light sensitive circuits on the chip. In this embodiment, the
`antenna and the center of the chip can be coplanar.
`FIG. 4 shows a top view of the thin RF ID tag 400. The
`chip 410 is located within a window 450 placed in a ?exible
`substrate 420. The chip 410 has contacts 425 which are
`connected to a antenna 430 contained on the substrate.
`FIG. 5 shows a top view of the thin RF ID tag 500. The
`chip 510 placed in the window 550 has contacts 525 which
`are connected to more than one folded dipole antenna 530
`and 531 contained on the substrate.
`FIG. 6 shows a top view of the thin tag 600. The
`semiconductor chip 610 is connected to a folded dipole
`antenna 630 by means of contacts 625. The antenna is
`contained in the substrate 620 as described above. A thin
`battery 660 is connected to the chip 610 by leads 661 and
`662 bonded at contacts 625.
`The battery has short connecting lines 661 and 662
`providing electrical continuity between the battery and the
`chip. The battery is placed adjacent to the chip, not stacked
`upon the chip. The battery thickness of about 0.25 mm keeps
`the battery ?exible. The antenna is designed such that it is
`also adjacent to the battery. There is no overlap. The wiring
`is kept in one plane and all of the elements (chip, battery,
`antenna) are coplanar; there is no stacking. As a result, the
`package is thin and ?exible.
`The bonding method for attaching batteries to prior art
`radio frequency tags include some of the techniques
`described below, i.e., soldering, conducting adhesive; and
`wire bonding. In addition, spot welding may be used. In spot
`welding, shown below in FIG. 7E, the battery connection
`pads are pressed to contacts on the substrate while a low
`voltage high-current pulse bonds the two metals together.
`In one preferred embodiment, the metallurgies on the
`battery, chip, and substrate are such that the battery attaching
`mechanism is consistent with the method and mechanism of
`the chip attachment. For example, use of tin plating on the
`substrate to enable chip bonding may preclude use of
`conductive adhesive to attach the battery but might allow
`use of gold plating to enable attaching of both.
`A more preferred embodiment used to make a thin ?exible
`rugged package uses robust chip attach techniques such as
`thermocompression (TC) bonding used in TAB (tape auto
`mated bonding) technology. Using TC bonding for the chip
`and spot welding for the battery is a novel combination of
`bonding techniques that enables attachment of the battery to
`a ?exible substrate 620. In one preferred embodiment, the
`substrate is a TAB polyimide or polyester.
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`FIG. 7 shows different types of bonding available in the
`prior art to attach chips to circuitry that are on the substrate
`when producing an RF tag. These include thermocompres
`sion bonding, ultrasonic single point bonding, soldering, and
`conductive adhesive.
`In FIG. 7A, using thermocompression bonding, suitable
`metal surfaces are brought into contact with pressure 750
`and heat 740 applied by therrnode 720 to form a metal-to~
`metal bond 760 usually gold bumps 730 on chip 710 to
`gold~plated leads 706 on substrate 705 which rests on lower
`thermode 780. Many leads are bonded at once (gang bond
`ing). This is used extensively for reel-to-reel TAB (tape
`automated bonding).
`FIG. 7B shows ultrasonic singlepoint bonding a variation
`on thermocompression bonding for TAB where some ultra
`sonic energy is substituted for some pressure. One bond is
`done at a time. This bonding type also requires gold-to-gold
`metallurgy. Bonding tip 751 applies pressure 731 and ultra
`sonic energy 741 while pressing lead 721 to bump 725 on
`chip 711 resting on lower support 705.
`FIG. 7C shows soldering or C4 solderbonding where
`small lead/tin solder bumps 746 are used as the connecting
`medium between chip 716 and pads 726 on substrate 736.
`The re?ow is carried out while the substrate is carried on
`platform 756 through oven 786. This usually requires the
`application of solder flux for re?ow of the solder at elevated
`temperature.
`FIG. 7D shows conducting adhesive bonding where a
`metal-?lled adhesive 744 is applied to form the connecting
`medium between chip pads 740 on chip 714 and the sub
`strate pads 724 on the substrate 734. Heat 774 and pressure
`784 are applied by pressing between thermodes 764 and 754.
`FIG. 7E shows spot welding where welding tips 755 and
`765 separated by gap 775 are pressed to conductor 745 held
`in contact with conductor 735 placed on insulating substrate
`725. Current 785 beats the welding tips 755 and 765 to make
`the bond.
`FIG. 8 shows an RF postage stamp 800 containing a thin
`RF tag 810 which consists of antenna 815, battery 820, and
`chip 830 a?ixed to envelope or package 840. This tag 810
`can be any of the embodiments described above. In this
`application, the cover (typically 270 of FIG. 2 and 370 of
`FIG. 3) for the tag is the paper of the stamp. Adhesives, such
`as acrylics, are used to sandwich the tag between thin paper.
`These adhesives would correspond to the layer 250 in FIG.
`2 and 350 in FIG. 3. The top surface (of one side 270, 370)
`can be printed with the appropriate graphics while the
`bottom surface has a pressure sensitive adhesive (of the
`other side 270, 370 in the case of a tag laminated on two
`sides), also acrylic, to bond the stamp to a package or letter
`envelope. The RF tag would contain information about
`mailing used to track'a letter or parcel on which the stamp
`is placed. Alternatively, the RF tag 850 could be enclosed in
`the parcel membrane or in the wall of the envelop 840. In
`another, embodiment the RF tag could be placed within the
`parcel or envelop.
`FIG. 9 shows the thin RF tag 920 embedded in the cover
`910 of passport 930 to form an RF passport 900. Here the tag
`is sandwiched between the paper covers of the passport. The
`tag can have an environmental larninate(s) (270, 370) as
`described above or alternatively, the passport cover can be
`used as the tag larninate(s) (270, 370). The tag contains in its
`memory information on the identity of the passport owner,
`visas, dates of entry, restrictions, or any other desirable
`information. The information may be in encrypted form for
`added security. The encryption “key” would be a software
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`code that is held and used solely by the agency issuing the
`passport. The deencryption key may be made public so that
`anyone (with a public deencryption key) can read informa
`tion in the memory of the tag but only the agency having the
`encryption key can write information to the tag.
`FIG. 10 shows admission ticket 1010 containing RF tag
`1020. The tag is again enclosed between paper covers or
`other laminates. The ticket may be a simple admission ticket
`or entitlement such as an airline ticket or a food stamp.
`However, the tagged ticket may also serve as a tracking
`device.
`FIG. 11 shows a CD 1140 enclosed in box 1120 with an
`RF ID antitheft tag 1130 a?ixed to the box 1120. The tag
`serves as both a barcode replacement, inventory device,
`point of sale device, and as an antitheft device. Information
`on product variety, price, date of manufacture and sale may
`be carried by the tag. Additional bits of information in the
`memory of the circuit may be changed at the time of sale to
`indicated that the item may be taken from the store.
`FIG. 12 shows ISO standard credit card 1210 containing
`an RF tag 1220. The credit card may serve as an ATM card,
`frequent ?yer card, library card, phone card, employee ID,
`medical ID card, gasoline credit card or any credit or debit
`card. The covers (laminates 270, 370) of the tag could be the
`covers of the credit card, preferably PVC laminations. The
`core of the credit card, 0.5 mm thick, has a window placed
`in it at the time of manufacture. The 0.5 mm thick tag
`package is placed in the window and then sealed into the
`card. The resulting credit card, including the tag, will not
`only have the length and width that meet the ISO standard,
`but the thickness as well.
`In another embodiment of the present invention, shown in
`FIG. 13, the RF tag 1320 is place within a vehicular drivers
`license 1310 in the same manner as described above. This
`allows information on the RF tag to be used for personal
`identi?cation, driving record, organ donor information,
`restrictions, proof of identity and age, etc. The information
`can be encrypted for security purposes.
`We claim:
`1. A thin ?exible electronic radio frequency tag circuit
`Comprising;
`a. an insulating, ?exible substrate;
`b. an antenna that is an integral part of the substrate and
`that has terminals;
`c. a circuit chip having a modulator circuit, a logic circuit,
`a memory circuit, and chip connectors and being on the
`substrate in adjacent proximity to the antenna;
`d. one or more connecting lines between the antenna
`terminals and the chip connectors, the connecting lines
`being coplanar with the antenna and antenna terminals.
`2. A circuit, as in claim 1, wherein the substrate is organic.
`3. A circuit, as in claim 2, wherein the substrate is
`polyimide.
`4. A circuit, as in claim 2, wherein the substrate is
`polyester.
`5. A circuit, as in claim 1, wherein the connecting lines are
`bonded to the chip connectors using any of the bonding
`types including thermal compression, single point bonding,
`C4 bonding, and conductive adhesive.
`6. A circuit, as in claim 1, wherein the substrate has an
`aperture into which the chip is placed.
`7. A circuit, as in claim 1, wherein the chip is covered by
`an encapsulant.
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`8. A circuit, as in claim 7, wherein the encapsulant is
`opaque.
`9. A circuit, as in claim 7, wherein an organic cover
`surrounds the chip, the encapsulant, the substrate, and the
`antenna.
`10. A circuit, as in claim 9, wherein the organic cover is
`one of the materials including polyester, mylar, polyimide,
`and polyethylene.
`11. A circuit, as in claim 1, that is laminated by one or
`more layers.
`12. A circuit, as in claim 11, that is laminated by a two
`layer laminate comprising a hard outer layer and a adhesive
`inner layer.
`13. A circuit, as in claim 12, wherein the adhesive is one
`of the materials including ethyl vinyl acetate (EVA), phe
`nolic butyral, and silicone adhesive.
`14. A circuit, as in claim 11, wherein the circuit is
`laminated on one side.
`15. A circuit, as in claim 11, wherein the circuit is
`laminated on two sides.
`16. A circuit, as in claim 11, wherein the circuit has at least
`one tag dimension that is less than 760 microns (30 mils).
`17. A circuit, as in claim 16, that is encapsulated as an
`International Organization for Standardization (ISO) stan
`dard credit card size package.
`18. A circuit, as in claim 1, wherein the antenna is a
`resonant antenna and is any one of the following structures
`including folded dipole, dipole, and loop.
`19. A circuit, as in claim 1, wherein a battery is also
`affixed to the substrate in adjacent proximity to the antenna
`and chip and is connected by one or more battery connecting
`lines to two or more chip battery contacts wherein the
`battery connecting lines and the battery contacts are copla
`nar with the antenna and connecting lines.
`20. A circuit, as in claim 19, wherein the battery contacts
`are connected to the battery connecting lines by any of the
`bonding types including spot welding, soldering, thermo
`compression bonding, and conducting adhesive.
`21. A circuit, as in claim 19, wherein the battery contacts
`are connected by spot welding and the chip contacts are
`connected to the antenna by therrnocompression bonding.
`22. A circuit, as in claim 1, wherein the chip has at least
`one chip dimension less than 300 microns (12 mils), the
`antenna has at least one antenna dimension less than 35
`microns (1.4 mils), and the substrate has at least one
`substrate dimension less than 125 microns (5 mils) whereby
`the circuit has at least one circuit dimension less than 508
`microns (20 mils).
`23. A circuit, as in claim 22, wherein the chip memory has
`information about mailing and the circuit is applied to a
`mailed letter or parcel.
`24. A circuit, as in claim 23, wherein the RF tag is
`enclosed within a stamp.
`25. A circuit, as in claim 23, wherein the RF tag is
`enclosed within the parcel or envelop membrane.
`26. A circuit, as in claim 22, wherein the tag is enclose