Radio frequency communication apparatus and methods of forming a radio frequency communication apparatus

A method of forming a radio frequency communication apparatus includes providing a substrate provided with an outermost surface. An RFID is adhered at least partially within the substrate, and the RFID includes an antenna and an integrated circuit. The RFID and substrate together form a radio frequency communication apparatus. A method of forming a radio frequency communication apparatus includes providing a substrate with a frontside surface. An opening is formed through the frontside surface and into the substrate. An RFID is inserted within the opening and adhered to the substrate within the opening. The RFID includes an antenna and an integrated circuit to form a radio frequency communication apparatus.

TECHNICAL FIELD
 The invention pertains to radio frequency communication apparatuses and to
 methods of forming radio frequency communication apparatuses.
 BACKGROUND OF THE INVENTION
 Radio frequency communication apparatuses are devices configured for
 communicating with other devices through radio frequencies. Radio
 frequency communication apparatuses can comprise radio frequency
 identification devices (RFIDS). RFIDs are described in detail in U.S.
 patent application Ser. No. 08/705,043, filed Aug. 29, 1996, and
 incorporated herein by reference. RFIDs can comprise wireless
 communication circuitry or transponder circuitry for providing wireless
 communications with an interrogator unit. RFIDs can comprise integrated
 circuit chips. Such chips can contain, for example, a processor and
 memory. RFIDs comprising integrated circuitry may be referred to as
 intelligent RFIDs or as remote intelligent communication (RIC) devices.
 Radio frequency communication apparatuses can further comprise transmit
 and receive antennas electrically connected with an RFID. The antennas can
 be suitable for respectively transmitting and receiving wireless signals
 or RF energy.
 Incorporating RFIDs into radio frequency communication apparatuses can be
 laborious and expensive. Accordingly, it is desirable to develop
 alternative methods for incorporating RFIDs into radio frequency
 communication apparatuses.
 SUMMARY OF THE INVENTION
 In one aspect, the invention encompasses a method of forming a radio
 frequency communication apparatus. A substrate is provided. The substrate
 has an outermost surface. An RFID is adhered to the substrate outermost
 surface. The RFID comprises an antenna and an integrated circuit. An
 entirety of the RFID is received outwardly of the substrate outermost
 surface.
 In another aspect, the invention encompasses a method of forming a radio
 frequency communication apparatus. A substrate is provided. The substrate
 has a frontside surface. An opening is formed through the frontside
 surface and into the substrate. An RFID is inserted within the opening.
 The RFID is adhered to the substrate within the opening. The RFID
 comprises an antenna and an integrated circuit.
 In another aspect, the invention encompasses a radio frequency
 communication apparatus. The apparatus comprises a substrate having an
 outermost surface. The apparatus further comprises an RFID adhered to the
 substrate outermost surface. The RFID comprises an antenna and an
 integrated circuit. An entirety of the RFID is received outwardly of the
 substrate outermost surface.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
 This disclosure of the invention is submitted in furtherance of the
 constitutional purposes of the U.S. Patent Laws "to promote the progress
 of science and useful arts" (Article 1, Section 8).
 FIG. 1 illustrates a radio frequency communication apparatus 10 of the
 present invention. Device 10 comprises a substrate 12 and an RFID 14
 proximate substrate 12. Substrate 12 can comprise a card having length and
 width dimensions corresponding to those of a credit card, and can comply
 with ISO 7816. For example, substrate 12 can have a length of from about
 0.8 inch to about 6.75 inches, a width of from about 0.5 inch to about
 4.25 inches, and a thickness of from about 0.010 inch to about 0.20 inch.
 Further, substrate 12 can comprise polyester, PVC and/or ABS, and can be
 substantially homogenous throughout an entirety of its construction.
 Substrate 12 consists of four peripheral quadrants, "A", "B", "C", and
 "D". Such four quadrants have substantially equal areas relative to one
 another. In the shown embodiment, RFID 14 is entirely contained within the
 quadrant "A".
 RFID 14 can be a chip comprising an integrated circuit and an antenna, and
 configured for communicating with an interrogator. RFID 14 will preferably
 also comprise a battery in electrical communication with the integrated
 circuit. Alternatively, as shown in FIG. 7, RFID 14 can comprise a
 substrate 70 upon which is adhered an integrated circuit chip 72, an
 antenna 74, and a battery 76. Chip 72 and battery 76 are electrically
 interconnected to one another through conductive interconnects 78. Chip
 72, battery 76 and antenna 74 can be covered with a protective surface,
 such as, for example, an encapsulant. Such protective surface can be
 provided prior to adhering RFID 14 to substrate 12, or after adhering RFID
 14 to substrate 12.
 In accordance with the present invention, RFID 14 can be mounted to
 substrate 12 in a variety of configurations. A first of the configurations
 is illustrated in FIG. 2. Substrate 12 comprises a substantially planar
 outer surface 16 upon which is adhered RFID 14. An entirety of RFID 14 is
 thus received outwardly of substrate outermost surface 16. In the shown
 embodiment, RFID 14 covers a portion 18 of outer surface 16 and leaves
 another portion 20 uncovered, or exposed. In alternative embodiments which
 are not shown, RFID 14 can cover an entirety of outer surface 16. RFID 14
 can be adhered with, for example, an epoxy adhesive.
 A second embodiment configuration of a radio frequency communication
 apparatus of the present invention is illustrated in FIG. 3. In referring
 to FIG. 3, similar numbering to that used above in describing FIGS. 1 and
 2 is utilized, with differences indicated by the suffix "a" or by
 different numerals. Radio frequency communication apparatus 10a comprises
 a substrate 12a having a frontside surface 22 and a backside surface 24.
 An opening 26 is formed through frontside surface 22 and into substrate
 12a. Opening 26 can be formed, for example, by molding the opening within
 substrate 12a as substrate 12a is formed. As another example, opening 26
 can be formed by cutting the opening into substrate 12a after substrate
 12a is formed. Opening 26 extends only partially into substrate 12a and
 comprises a periphery defined by an interior bottom surface 28 and by
 interior side surfaces 30.
 An RFID 14a is inserted within opening 26 and adhered to substrate 12a.
 RFID 14 has laterally outwardmost surfaces 31 laterally inward of interior
 side surfaces 30. RFID surfaces 31 can be abutted against interior side
 surfaces 30, but are more preferably displaced from the side surfaces 30
 as shown. RFID surfaces 31 are preferably displaced from side surfaces 30
 by a distance of less than or equal to about 3 mils when RFID 14 is
 approximately centered within opening 26, and more preferably displaced by
 a distance of less than or equal to about 2 mils. Thus, if RFID 14 is
 abutted against a side surface 30, rather than being approximately
 centered within opening 26, the largest gap between a surface 31 and a
 side surface 30 will preferably be less than or equal to about 6 mils, and
 more preferably less than or equal to about 4 mils. The gaps between RFID
 surfaces 31 and side surfaces 30 can receive a bonding adhesive to adhere
 RFID 14 to substrate 12a. RFID 14a can be adhered to substrate 12a by
 adhesive applied to bottom surface 28 and/or to side surfaces 30.
 RFID 14a comprises a top surface 32. In the shown embodiment, top surface
 32 is above frontside surface 22 of substrate 12a. In alternate
 embodiments, top surface 32 of RFID 14a can be below frontside surface 22,
 or substantially flush with frontside surface 22. Such alternative
 embodiments can be formed by extending opening 26 further into substrate
 12a than shown, or by utilizing a substrate 12a which is thicker relative
 to RFID 14a than the shown configuration.
 A third embodiment configuration of a radio frequency communication
 apparatus of the present invention is described with reference to FIG. 4.
 In referring to FIG. 4, similar numbering to that used in describing FIGS.
 1-3 is utilized, with differences indicated by the suffix "b" or by
 different numerals. FIG. 4 is a cross-sectional view along the same line
 as that of FIG. 2. FIG. 4 illustrates a radio frequency communication
 apparatus 10b comprising a substrate 12b and an opening 26b extending
 entirely through substrate 12b. RFID 14b comprises a top surface 32b and a
 bottom surface 34. Top surface 32b is substantially flush with frontside
 surface 22b of substrate 12b, and bottom surface 34 is substantially flush
 with backside surface 24b of substrate 12b. In alternative embodiments,
 top surface 32b can extend above or below frontside surface 22b, and
 bottom surface 34 can extend above or below backside surface 24b.
 As shown in FIG. 8, opening 26b comprises a rectangular shaped internal
 periphery defined by sides 30b. RFID 14b comprises an external periphery
 having a rectangular shape complementary to the internal periphery shape
 of opening 26b. The external periphery of RFID 14b is defined by sides
 31b. Each of sides 31b is proximate a side 30b. RFID 14b is preferably
 sized relative to opening 26b such that each of sides 31b is within about
 3 mils of a proximate side 30b when RFID 14b is approximately centered
 within opening 26b. More preferably, RFID 14b is sized relative to opening
 26b such that each of sides 31b is within about 2 mils of a proximate side
 30b when RFID 14b is approximately centered within opening 26b. In
 practice, RFID 14b is placed within opening 26b with a mechanized system
 and adhered to substrate 12b, with, for example, epoxy. The slight
 displacement of sides 31b from sides 30b enables the epoxy to squeeze into
 gaps between sides 31b and 30b and adhere sides 31b and 30b to one
 another.
 Radio frequency communication apparatus 12b can be further processed as
 shown in FIG. 5. Laminating films 36 and 38 are provided over frontside
 surface 22b and backside surface 24b, respectively, of substrate 12b.
 Laminating films 36 and 38 extend over top surface 32b and bottom surface
 34, respectively, of RFID 14b. Laminating films 36 and 38 can comprise,
 for example, thin plastic sheets adhesively, or thermally, adhered to
 substrate 12b and RFID 14b.
 Laminating films 36 and 38 protect RFID 14b and substrate 12b. Also,
 laminating films 36 and 38 can aid in retaining RFID 14b within substrate
 12b. Further, laminating films 36 and 38 can be printed with a message
 which is to be displayed on radio frequency communication apparatus 10b.
 Such message can be, for example, a set of instructions for use of radio
 frequency device 10b, or advertising. Laminating films 36 and 38 can both
 be formed after insertion of RFID 14b within substrate 12b. Alternatively,
 one of laminating films 36 or 38 can be formed before insertion of RFID
 14b within substrate 12b and the other of laminating films 36 and 38 can
 be formed after such insertion.
 Although laminating films are shown formed over both frontside surface 22b
 and backside surface 24b, in alternative embodiments a laminating film can
 be formed over only one of surfaces 22b and 24b. Also, although laminating
 films 36 and 38 are shown extending entirely over surfaces 32b, 22b, 24b
 and 34, in alternative embodiments the laminating films may be formed to
 extend only partially over one or more of surfaces 32b, 22b, 34 and 24b.
 Laminating films 36 and 38 preferably extend entirely over surfaces 32b
 and 34 and at least over portions of surfaces 22b and 24b which are
 proximate to surfaces 32b and 34.
 An alternative construction of a radio frequency communication apparatus of
 the present invention is described with reference to FIG. 6. In referring
 to FIG. 6, similar numbering to that used above in describing FIGS. 1-5 is
 utilized, with differences indicated by the suffix "c" or by different
 numerals. Radio frequency communication apparatus 10c comprises a
 substrate 12c having an opening 26c formed therethrough. Within opening
 26c is an RFID 14c. RFID 14c has a top surface 32c which is above
 frontside surface 22c of substrate 12c. Radio frequency communication
 apparatus 10c further comprises a laminating film 38c formed over a
 backside surface 24c of substrate 12c and over a bottom surface 34c of
 RFID 14c. Laminating film 38c may be formed before or after insertion of
 RFID 14c within opening 26c. In alternative embodiments of the invention,
 a second laminating film could be formed over top surface 32c of RFID 14c
 and over frontside surface 22c of substrate 12c.
 The invention arose out of needs specifically associated with RFIDs.
 However, the artisan will appreciate that the invention can have
 application to smart cards.
 In compliance with the statute, the invention has been described in
 language more or less specific as to structural and methodical features.
 It is to be understood, however, that the invention is not limited to the
 specific features shown and described, since the means herein disclosed
 comprise preferred forms of putting the invention into effect. The
 invention is, therefore, claimed in any of its forms or modifications
 within the proper scope of the appended claims appropriately interpreted
 in accordance with the doctrine of equivalents.