Coupling frames for RFID devices

• US 10,248,902 B1
• Filed: 11/06/2017
• Issued: 04/02/2019
• Est. Priority Date: 11/06/2017
• Status: Active Grant

• Current Assignee: AmaTech Group Limited (Paragon Group Limited)
• Original Assignee: Féinics AmaTech Teoranta (Paragon Group Limited)
• Inventors: Finn, David, Lotya, Mustafa, Molloy, Darren
• Primary Examiner(s): Ly, Toan
• Application Number:
  US15/803,866
• Time in Patent Office: 512 Days
• Field of Search: 235492
• CPC Class Codes: B23K 2101/40 Semiconductor devices
• CPC Class Codes: B23K 26/361 for deburring or mechanical trimming B23K26/351 takes precedence
• CPC Class Codes: G06K 19/077 Constructional details, e.g. mounting of circuits in the carrier
• CPC Class Codes: G06K 19/07722 the record carrier being multilayered, e.g. laminated sheets flat articles in general, see B32B37/00
• CPC Class Codes: G06K 19/07747 at least one of the integrated circuit chips being mounted as a module
• CPC Class Codes: G06K 19/07749 the record carrier being capable of non-contact communication, e.g. constructional details of the antenna of a non-contact smart card
• CPC Class Codes: G06K 19/07769 the further communication means being a galvanic interface, e.g. hybrid or mixed smart cards having a contact and a non-contact interface
• CPC Class Codes: G06K 19/07794 the record carrier comprising a booster or auxiliary antenna in addition to the antenna connected directly to the integrated circuit
• CPC Class Codes: H01L 2224/05554 being square
• CPC Class Codes: H01L 2224/16225 the item being non-metallic, e.g. insulating substrate with or without metallisation
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2224/48227 connecting the wire to a bond pad of the item
• CPC Class Codes: H01L 23/49855 for flat-cards, e.g. credit cards cards per se G06K19/00
• CPC Class Codes: H01L 24/16 of an individual bump connector
• CPC Class Codes: H01L 24/48 of an individual wire connector
• CPC Class Codes: H01L 2924/00014 the subject-matter covered by the group, the symbol of which is combined with the symbol of this group, being disclosed without further technical details
• CPC Class Codes: H01L 2924/19107 off-chip wires
• CPC Class Codes: H01Q 1/2225 used in active tags, i.e. provided with its own power source or in passive tags, i.e. deriving power from RF signal
• CPC Class Codes: H01Q 1/38 formed by a conductive layer on an insulating support patch antennas H01Q9/0407; microstrip dipole antennas H01Q9/065; microstrip slot antennas H01Q13/106; transmission line microstrip antennas H01Q13/206; manufacturing reflecting surfaces using insulating material for supporting the reflecting surface H01Q15/142
• CPC Class Codes: H01Q 7/00 Loop antennas with a substantially uniform current distribution around the loop and having a directional radiation pattern in a plane perpendicular to the plane of the loop

Abstract

A transponder chip module (TCM) comprises an RFID chip (CM, IC), optionally contact pads (CP), a module antenna (MA), and a coupling frame (CF), all on a common substrate or module tape (MT). The coupling frame (CF) may be in the form of a conductive layer having an outer edge (OE) and a slit (S) or non-conductive stripe (NCS) extending from the outer edge to an inner position thereof which may be a central opening (OP). The coupling frame (CF) may be arranged so that the slit (S) or non-conductive strips (NCS) overlaps at least a portion of the module antenna (MA). A suppressor diode or capacitor may be connected across the slit (S). Methods and apparatus are disclosed.

Claims

1. An RFID device comprising:

a transponder chip module (TCM) comprising an RFID chip (IC) and a module antenna (MA); and

a coupling frame (CF) comprising a conductive surface and having an electrical discontinuity comprising a slit (S) or non-conductive stripe (NCS) extending through the surface from an outer edge thereof to an inner position thereof, wherein the coupling frame is disposed so that the slit (S) or non-conductive stripe (NCS) overlaps at least a portion of the module antenna (MA), further comprising a capacitor connected across the slit (S).

2. The RFID device of claim 1, wherein the coupling frame (CF) is disposed in a card body (CB) of a smart card (SC).

3. The RFID device of claim 1, wherein the coupling frame (CF) is disposed on a module tape (MT) of the transponder chip module (TCM).

4. The RFID device of claim 1, wherein the slit (S) or non-conductive stripe (NCS) extends to an opening (OP) in the coupling frame (CF).

5. The RFID device of claim 1, wherein the slit (S) or non-conductive stripe (NCS) extends to an interior position of the coupling frame (CF).

6. The RFID device of claim 1, wherein the slit (S) or non-conductive stripe (NCS) overlaps at least some turns of the module antenna (MA).

7. The RFID device claim 1, wherein:

the transponder chip module (TCM) includes a module tape (MT) supporting the RFID chip (IC) and module antenna (MA); and

the coupling frame (CF) is disposed on an opposite side of the module tape (MT) from the module antenna (MA, PA).

8. The RFID device claim 1, wherein:

the transponder chip module (TCM) includes a module tape (MT) supporting the RFID chip (IC) and module antenna (MA); and

the coupling frame (CF) is formed from a conductive layer (CL) on the module tape (MT) which is one of the (i) conductive layer used to form contact pads (CP) on the face-up side of the module tape (MT) and (ii) the conductive layer used to form the module antenna on the face-down side of the module tape (MT).

9. The RFID device claim 1, wherein:

the module antenna (MA) comprises an etched planar antenna (PA) having a number of tracks (traces) separated by spaces;

wherein;

a track width is less than 100 μ

m; and

a spacing between adjacent tracks is less than 75 μ

m.

10. The RFID device of claim 1, further comprising:

a capacitor (CAP) connected with the module antenna (MA) or with terminals of the RFID chip (IC).

11. The RFID device of claim 1, wherein the capacitor comprises a silicon capacitor.

12. A method of improving coupling between an RFID device comprising a transponder chip module (TCM) and an external reader, the transponder chip module (TCM) comprising an RFID chip (IC, CM) and a module antenna (MA), characterized by:

providing an open-loop conductive coupling frame (CF), wherein the coupling frame (CF) has a slit (S) or non-conductive stripe (NCS) extending from an outer edge (OE) thereof to an interior position thereof and coupling frame (CF) is positioned so that the slit (S) or non-conductive stripe (NCS) overlaps at least a portion of the module antenna (MA, PA, LES); and

connecting a suppressor diode or capacitor across the slit (S).

13. The method of claim 12, wherein:

the coupling frame (CF) has an opening (OP) at the interior position thereof, and the opening defines an inner edge (IE) of the coupling frame (CF); and

the slit (S) or non-conductive stripe (NCS) extends from the opening (OP) to the outer edge (OE) of the coupling frame (CF).

14. The method of claim 12, wherein the coupling frame is incorporated into the transponder chip module (TCM).

15. In conjunction with an RFID device comprising an antenna having a number of tracks or turns separated by spaces, a coupling frame (CF) comprising a conductive surface and having an electrical discontinuity comprising a slit (S) or non-conductive stripe (NCS) extending through the surface from an outer edge thereof to an inner position thereof, wherein the coupling frame is disposed so that the slit (S) overlaps at least a portion of the module antenna (MA);

further comprising a capacitor connected across the slit (S).