On die RFID tag antenna

• US 20060202831A1
• Filed: 02/28/2005
• Published: 09/14/2006
• Est. Priority Date: 02/28/2005
• Status: Active Grant

• Current Assignee: Impinj, Inc.
• Original Assignee: Impinj, Inc.
• Inventors: Horch, Andrew E.
• Granted Patent: US 7,528,724 B2
• Time in Patent Office: Days
• US Class Current: 340/572.700
• 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 7/0095 Testing the sensing arrangement, e.g. testing if a magnetic card reader, bar code reader, RFID interrogator or smart card reader functions properly testing of electrical circuits G01R31/28
• CPC Class Codes: H01L 23/5227 Inductive arrangements or effects of, or between, wiring layers other inductive arrangements H01L23/645
• CPC Class Codes: H01L 23/585 comprising conductive layers or plates or strips or rods or rings H01L23/60, H01L23/62, H01L23/64, H01L23/66 take precedence
• 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 2924/0002 Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00
• CPC Class Codes: H01L 2924/3011 Impedance

Abstract

Wirelessly testing an RFID tag before it is packaged or otherwise entered into a process reserved for “working” RFID tags is described. Various processes that employ such wireless testing as well as various “on-die” RFID tag antennae designs for facilitating the wireless testing are also described.

Claims

1. An RFID tag comprising:

a) an active device area comprising transistors;

b) an on-die antenna having wiring that resides outside said active device area; and

,

c) a conductive path that runs from said on-die antenna to said active device area.

2. The apparatus of claim 1 wherein said on-die antenna winds around said active device area.

3. The apparatus of claim 2 wherein said on-die antenna is electrically isolated from said RFID tag'"'"'s die seal ring.

4. The apparatus of claim 3 wherein at least a portion of said conductive path is embedded within said RFID tag'"'"'s semiconductor substrate, said conductive path being electrically coupled to said wiring and metal within said active device area.

5. The apparatus of claim 4 wherein said embedded portion of said conductive path comprises an N well.

6. The apparatus of claim 4 wherein said embedded portion of said conductive path comprises a P well.

7. The apparatus of claim 4 wherein said embedded portion of said conductive path comprises an N type source/drain region.

8. The apparatus of claim 4 wherein said embedded portion of said conductive path comprises a P source/drain region.

9. The apparatus of claim 4 wherein a PN junction exists between said embedded portion of said conductive path and said substrate'"'"'s bulk material.

10. The apparatus of claim 9 wherein a pair of PN junctions exist between said embedded portion of said conductive path and said substrate'"'"'s bulk material.

11. The apparatus of claim 3 wherein said conductive path runs above said RFID tag'"'"'s die seal ring, said conductive path electrically coupling said wiring and metal within said active device area.

12. The apparatus of claim 2 wherein said on-die antenna is comprised of a stacked structure comprising a bar via, a bar contact and a continuous wire to thwart penetration of contaminants into said active device area.

13. The apparatus of claim 12 wherein an open path exists along a semiconductor substrate surface of said RFID tag from a die edge of said RFID tag to said active device area, said open path not crossing through a stacked structure comprising a bar contact, a continuous wire and a bar via in order to reach said active device area.

14. The apparatus of claim 13 wherein a length of said first wiring does not make contact to a bar via or a bar contact.

15. The apparatus of claim 2 wherein a length of said wiring does not make contact to a bar via or a bar contact.

16. The apparatus of claim 1 wherein said on-die antenna is electrically isolated from said RFID tag'"'"'s die seal ring.

17. The apparatus of claim 16 wherein at least a portion of said conductive path is embedded within said RFID tag'"'"'s semiconductor substrate, said conductive path being electrically coupled to said wiring and metal within said active device area.

18. The apparatus of claim 1 wherein an open path exists along a semiconductor substrate surface of said RFID tag from a die edge of said RFID tag to said active device area, said open path not crossing through a stacked structure comprising a bar contact, a continuous wire and a bar via in order to reach said active device area.

19. The apparatus of claim 1 wherein said wiring serpentines back and forth in a same plane outside an edge of said RFID tag'"'"'s active device area.

20. The apparatus of claim 1 wherein said conductive path and said wiring are electrically coupled to said RFID tag'"'"'s die seal ring.

21. The apparatus of claim 20 wherein a PN junction exists beneath said RFID tag'"'"'s die seal ting.

22. The apparatus of claim 21 wherein a pair of PN junctions exist beneath said RFID tag'"'"'s die seal ring.

23. An RFID tag comprising an on-die antenna, said on-die antenna comprising wiring that resides outside said RFID tag'"'"'s active device area, an open path existing along a semiconductor substrate surface of said RFID tag from a die edge of said RFID tag to said active device area, said open path not crossing through a die seal ring structure in order to reach said active device area.

24. The RFID tag of claim 23 wherein said die seal ring comprises a stacked structure comprising a bar contact, a continuous wire and a bar via.

25. The apparatus of claim 23 wherein a length of said on-die antenna wiring does not make contact to a bar via or a bar contact, said length of said on-die antenna wiring also residing outside said active device area.

26. The apparatus of claim 23 wherein said on-die antenna winds around said active device area.

27. The apparatus of claim 23 wherein a PN junction exists beneath said wiring.

28. The apparatus of claim 23 wherein a pair of PN junctions exist beneath said wiring.

29. A semiconductor chip, comprising:

a) an active device area;

b) a die seal ring surrounding said active device area;

c) an antenna outside said die seal ring, said antenna electrically isolated from said die seal ring; and

,

d) a conductive path coupled to said antenna and wiring within said active device area, said conductive path electrically isolated from said die seal ring.

30. The semiconductor chip of claim 29 wherein said semiconductor chip is an RFID tag.

31. The semiconductor chip of claim 30 wherein said conductive path is embedded within said semiconductor chip'"'"'s semiconductor substrate beneath said die seal ring.

32. The semiconductor chip of claim 31 wherein said conductive path comprises an N well.

33. The semiconductor chip of claim 31 wherein said conductive path comprises a P well.

34. The semiconductor chip of claim 31 wherein said conductive path comprises an N source/drain region.

35. The semiconductor chip of claim 31 wherein said conductive path comprises a P source/drain region.

36. The semiconductor chip of claim 31 wherein said conductive path comprises an N region.

37. The semiconductor chip of claim 31 wherein said conductive path comprises a P region.

38. The semiconductor chip of claim 30 wherein said conductive path runs over said die seal ring without contacting said die seal ring.

39. The semiconductor chip of claim 38 wherein said wiring comprises copper wiring and said conductive path is formed with a metal capping layer used to deter copper wiring corrosion.

40. The semiconductor substrate of claim 39 wherein said metal capping layer comprises aluminum.