Tamper-proof RFID label

• US 8,991,709 B2
• Filed: 08/24/2011
• Issued: 03/31/2015
• Est. Priority Date: 08/30/2010
• Status: Expired due to Fees

• Current Assignee: TagStar Systems GmbH (Identiv, Inc.)
• Original Assignee: TagStar Systems GmbH (Identiv, Inc.)
• Inventors: Mieslinger, Stefan
• Primary Examiner(s): STANFORD, CHRISTOPHER J
• Application Number:
  US13/217,096
• Publication Number:
  US 20120145794A1
• Time in Patent Office: 1,315 Days
• Field of Search: 235/492, 3405721-5723
• US Class Current: 235/492
• CPC Class Codes: G06K 19/0723 the record carrier comprising an arrangement for non-contact communication, e.g. wireless communication circuits on transponder cards, non-contact smart cards or RFIDs
• CPC Class Codes: G06K 19/0739 the incapacitated circuit being part of an antenna
• 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 19/07779 the inductive antenna being a coil
• CPC Class Codes: G06K 19/07798 part of the antenna or the integrated circuit being adapted for rupturing or breaking, e.g. record carriers functioning as sealing devices for detecting not-authenticated opening of containers electronic seals G09F3/03
• CPC Class Codes: H01P 11/00 Apparatus or processes specially adapted for manufacturing waveguides or resonators, lines, or other devices of the waveguide type
• CPC Class Codes: Y10T 156/10 Methods of surface bonding and/or assembly therefor
• CPC Class Codes: Y10T 29/49002 Electrical device making
• CPC Class Codes: Y10T 29/49016 Antenna or wave energy "plumbing" making

Abstract

Described are RFID structures and methods for forming RFID structures. An RFID structure includes an antenna substrate and a loop antenna assembly positioned on the antenna substrate. The loop antenna assembly includes at least two contact pads and a plurality of antenna loop windings having an average spacing between adjacent antenna loop windings of the plurality of loop windings. The plurality of antenna loop windings define one or more gap regions that separate adjacent or adjoining antenna segments of the plurality of antenna loop windings by at least twice the average spacing.

Claims

1. A method of manufacturing a RFID structure, the method comprising:

providing an antenna substrate;

providing a loop antenna assembly on the antenna substrate, the loop antenna assembly comprising;

at least two contact pads; and

a plurality of antenna loop windings having an average spacing between adjacent antenna loop windings of the plurality of loop windings, the plurality of antenna loop windings defining a plurality of gap regions that separate adjacent or adjoining antenna segments of the plurality of antenna loop windings by at least twice the average spacing,

wherein the antenna substrate has a series of perforations and at least one perforation of the series of perforations is positioned directly beneath a segment of the plurality of antenna loop windings,

wherein separating one of the series of perforations results in dissection of the loop antenna assembly and renders the loop antenna assembly inoperable; and

wherein the perforations are formed by heating the antenna substrate using a laser after the loop antenna assembly has been positioned on the antenna substrate.

2. The method of claim 1, wherein the series of perforations comprise cuts, holes, slits, or any combination thereof.

3. The method of claim 1, wherein the plurality of antenna loop windings comprise one or more outer antenna loop windings and one or more inner antenna loop windings, at least one of the plurality of gap regions separates an antenna segment on an outermost winding of the one or more inner antenna loop windings with an adjacent antenna segment on an innermost winding of the one or more outer loop windings.

4. The method of claim 1, wherein the plurality of antenna loop windings comprises at least one track that includes two adjoining antenna segments that define lines having an angle less than 15 degrees and at least one of the plurality of gap regions is positioned between the two adjoining antenna segments.

5. The method of claim 4, wherein the at least one track comprises an outermost antenna loop winding of the plurality of antenna loop windings.

6. The method of claim 4, wherein the at least one track comprises an innermost antenna loop winding of the plurality of antenna loop windings.

7. The method of claim 1, wherein the average spacing is between 0.05 mm and 0.5 mm.

8. The method of claim 1, wherein the average spacing is between 0.08 mm and 0.12 mm.

9. The method of claim 1, wherein the one or more gap regions separate adjacent or adjoining antenna segments of the plurality of antenna loop windings by between 0.1 mm and 1.0 mm.

10. The method of claim 1, wherein the antenna substrate comprises a carrier foil including polyethylene terephthalate (PET), polyethylene terephthalate glycol-modified (PET-G), polypropylene (PP), polyethylene (PE), polyimide (PI), polyvinyl chloride (PVC), acrylonitrile butadiene styrene (ABS), liquid crystal polymer (LCP), polybutylene terephthalate (PBT), polyethylene naphthalate (PEN), glass fiber, epoxy, bismaleimide triazine (BT), polycarbonate (PC) or any combination thereof.

11. The method of claim 1 further comprising:

applying an adhesive layer on a surface of the antenna substrate opposite the loop antenna assembly;

coupling an integrated circuit to the at least two contact pads; and

applying a protective layer covering the loop antenna assembly and the integrated circuit.

12. The method of claim 1, wherein the RFID structure comprises a RFID label.

13. The method of claim 1, wherein the series of perforations are arranged in a wave pattern.