RFID tags and processes for producing RFID tags

• US 7,868,766 B2
• Filed: 02/05/2009
• Issued: 01/11/2011
• Est. Priority Date: 03/24/2003
• Status: Active Grant

• Current Assignee: RUIZHANG TECHNOLOGY LIMITED COMPANY
• Original Assignee: Alien Technology Corporation
• Inventors: Hadley, Mark A., Drzaic, Paul S., Schatz, Kenneth D., Pounds, Tom, Gengel, Glenn W.
• Primary Examiner(s): Mullen; Thomas J
• Application Number:
  US12/366,617
• Publication Number:
  US 20090167534A1
• Time in Patent Office: 705 Days
• Field of Search: 340/572.1, 340/572.7, 298/25, 298/29, 298/46, 438/106, 438/107, 438/110, 257/678, 257/734, 235/492, 361/737, 361/749, 361/760, 361/761, 361/764
• US Class Current: 340/572.7
• CPC Class Codes: D10B 2401/18 including electronic components
• CPC Class Codes: G06K 19/027 the material being suitable for use as a textile, e.g. woven-based RFID-like labels designed for attachment to laundry items markings attached to laundry items in general D06F93/00
• 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 19/07749 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 19/07758 arrangements for adhering the record carrier to further objects or living beings, functioning as an identification tag
• CPC Class Codes: H01L 2224/24227 the HDI interconnect not connecting to the same level of the item at which the semiconductor or solid-state body is mounted, e.g. the semiconductor or solid-state body being mounted in a cavity or on a protrusion of the item
• CPC Class Codes: H01L 2224/76155 Jetting means, e.g. ink jet
• CPC Class Codes: H01L 2224/82039 using a laser
• CPC Class Codes: H01L 2224/82102 using jetting, e.g. ink jet
• CPC Class Codes: H01L 24/24 of an individual high density interconnect connector
• CPC Class Codes: H01L 24/82 by forming build-up interconnects at chip-level, e.g. for high density interconnects [HDI] interconnection structure between a plurality of semiconductor chips H01L23/5389
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/01004 Beryllium [Be]
• CPC Class Codes: H01L 2924/01005 Boron [B]
• CPC Class Codes: H01L 2924/01027 Cobalt [Co]
• CPC Class Codes: H01L 2924/01033 Arsenic [As]
• CPC Class Codes: H01L 2924/01047 Silver [Ag]
• CPC Class Codes: H01L 2924/01051 Antimony [Sb]
• CPC Class Codes: H01L 2924/01079 Gold [Au]
• CPC Class Codes: H01L 2924/01082 Lead [Pb]
• CPC Class Codes: H01L 2924/014 : Solder alloys
• CPC Class Codes: H01L 2924/07802 : not being an ohmic electrical conductor
• CPC Class Codes: H01L 2924/12042 : LASER
• CPC Class Codes: H01L 2924/14 : Integrated circuits
• CPC Class Codes: H01L 2924/15153 : the die mounting substrate comprising a recess for hosting the device
• CPC Class Codes: H01L 2924/15165 : Monolayer substrate
• CPC Class Codes: H01L 2924/19041 : being a capacitor
• CPC Class Codes: H01L 2924/19042 : being an inductor
• CPC Class Codes: H01L 2924/3011 : Impedance
• CPC Class Codes: Y10T 29/49018 : with other electrical component
• CPC Class Codes: Y10T 29/49155 : Manufacturing circuit on or in base

Abstract

A Radio Frequency Identification (RFID) tag. The RFID tag comprises a flexible substrate and an integrated circuit embedded within the flexible substrate. The top surface of the integrated circuit is coplanar with the flexible substrate. At least one conductive element is formed on the flexible substrate. The conductive element is electrically connected to the integrated circuit. The conductive element serves as an antenna for the RFID tag.

Claims

1. An RFID tag comprising:

a flexible substrate;

an integrated circuit at least partially embedded within the flexible substrate, the integrated circuit having a top surface that is substantially coplanar with the flexible substrate;

conductive elements formed on the flexible substrate and electrically connected to the integrated circuit, the conductive elements also serving as an antenna for the RFID tag; and

wherein the conductive elements are formed on a top surface and bottom surface of the flexible substrate, and wherein an electrical connection is provided to connect a conductive element of the conductive elements on the bottom surface to the integrated circuit.

2. The RFID tag of claim 1 further comprising a planarization layer formed over the flexible substrate and the integrated circuit and wherein the electrical connection is formed through at least one via hole in the planarization layer.

3. The RFID tag of claim 1 wherein the electrical connection is formed by electrical connection around at least one side of the flexible substrate.

4. The RFID tag of claim 1 wherein a conductive element of the conductive elements formed on the top surface is connected to a pad on top of the integrated circuit.

5. The RFID tag of claim 4 wherein the conductive elements formed on the top surface and on the bottom surface form electrical loop structures, or inductive elements for the RFID tag.

6. The RFID tag of claim 1 wherein a first one of the conductive elements is electrically and mechanically coupled to a first pad on the integrated circuit and a second one of the conductive elements is electrically and mechanically coupled to a second pad on the integrated circuit (IC).

7. The RFID tag of claim 6 wherein the flexible substrate has a length which is at least 10 times the width of a receptor site for the IC and has a form factor of a thread.

8. The RFID tag of claim 7 wherein the antenna formed by the conductive elements is configured to have an impedance that substantially matches an input impedance of the IC.

9. An RFID tag comprising:

an RFID integrated circuit (IC) deposited in a flexible substrate;

a first antenna layer coupled to the RFID integrated circuit; and

a second antenna layer coupled to the RFID integrated circuit, wherein the first antenna layer is above the RFID integrated circuit and the second antenna layer is below the RFID integrated circuit, wherein the RFID integrated circuit is coupled to the first antenna layer at a first contact of the RFID integrated circuit and the RFID integrated circuit is coupled to the second antenna layer at a second contact of the RFID integrated circuit,

wherein the flexible substrate has a form factor of a thread.

10. An RFID tag comprising:

an RFID integrated circuit (IC) deposited in a flexible substrate;

a first antenna layer couples to the RFID integrated circuit; and

a second antenna layer coupled to the RFID integrated circuit, wherein the first antenna layer is above the RFID integrated circuit and the second antenna layer is below the RFID integrated circuit wherein the RFID integrated circuit is coupled to the first antenna layer at a first contact of the RFID integrated circuit and the RFID integrated circuit is coupled to the second antenna layer at a second contact of the RFID integrated circuit,

wherein a portion of the first antenna layer is electrically and mechanically coupled to a first pad on the IC and a portion of the second antenna layer is electrically and mechanically coupled to a second pad on the IC, and

wherein a size of the first pad is about the same size as a top surface of the IC, and wherein a size of the second pad is about the same size as a bottom surface of the IC.

11. An RFID tag comprising:

an RFID integrated circuit (IC) deposited in a flexible substrate;

a first antenna layer coupled to the RFID integrated circuit; and

a second antenna layer coupled to the RFID integrated circuit, wherein the first antenna layer is above the RFID integrated circuit and the second antenna layer is below the RFID integrated circuit, wherein the RFID integrated circuit is coupled to the first antenna layer at a first contact of the RFID integrated circuit and the RFID integrated circuit is coupled to the second antenna layer at a second contact of the RFID integrated circuit,

wherein the flexible substrate comprises a receptor for the IC and wherein an angular orientation of the IC is not fixed by the receptor.

12. The RFID tag of claim 11 wherein the angular orientation is capable of being a plurality of different orientations.