RFID device and method of forming
A radio frequency identification (RIFD) inlay includes an interposer that has a chip, and an antenna on an antenna substrate. The antenna substrate has a recess or hole, and the chip is at least partially in the recess or hole. By placing the chip or the interposer face down and at least partially in a recess or hole, thickness of the inlay may be reduced.
1. A radio frequency identification (REID) device comprising:
an antenna substrate having at least a recess therein;
an antenna on the antenna substrate; and
an interposer, wherein the interposer includes:
an RFID chip having contacts thereupon; and
interposer leads operatively coupled to the contacts of the chip;
wherein the interposer leads and the antenna are electrically coupled together;
wherein at least part of the interposer is within the at least a recess; and
wherein the interposer leads and the antenna are capacitively coupled together across a dielectric material.
2. The device of claim 1 , wherein the dielectric material is a dielectric layer.
3. The device of claim 1 , wherein the dielectric material is an adhesive layer.
4. The device of claim 1 , wherein the at least a recess is bounded by a thinned portion of the antenna substrate.
5. The device of claim 1 , wherein the at least a recess is a hole through the antenna substrate.
6. The device of claim 5 , wherein the hole is a punched hole through the antenna substrate.
7. The device of claim 5 , wherein part of the interposer passes through the hole.
8. The device of claim 7 ,
wherein the interposer leads are on a first side of the antenna substrate; and
wherein at least part of the chip is on an opposite side of the antenna substrate.
9. The device of claim 5 , wherein no part of the interposer passes fully though the hole.
10. The device of claim 5 , wherein the hole is a variable-dimension chip-receiving hole that is configured to expand to receive the at least part of the chip.
11. The device of claim 10 ,
wherein the interposer includes a pair of protruding posts on opposite respective sides of the chip; and
wherein the antenna substrate has a pair of variable-dimension post-receiving holes that receive the posts therein.
12. The device of claim 11 , wherein portions of the interposer leads on the posts are located in the post-receiving holes.
13. The device of claim 12 , wherein the portions of the interposer leads on the posts are in contact with electrically conductive material on inner edges of the post-receiving holes.
14. The device of claim 11 , wherein the posts are mechanically clamped by the antenna substrate at the post-receiving holes.
15. The device of claim 1 , wherein the chip has a greater thickness than that of the antenna substrate.
16. The device of claim 1 , wherein the chip has a greater thickness than that of the remainder of the interposer.
17. The device of claim 1 wherein the interposer also includes an interposer substrate that is mechanically coupled to the interposer leads.
18. The device of claim 17 , wherein the interposer substrate seals an open end of the at least a recess in the antenna substrate.
19. The device of claim 18 ,
wherein the at least a recess is a recess overlying a thinned portion of the antenna substrate; and
wherein the chip is enclosed between the interposer substrate and the thinned portion of the antenna substrate.
20. A method of forming an RFID device, the method comprising:
forming an interposer, wherein the forming includes electrically coupling interposer leads of the interposer to contacts of an RFID chip of the interposer;
forming at least a recess in an antenna substrate that has an antenna thereupon; and
subsequent to the forming at least a recess, mechanically coupling the interposer and the antenna substrate together;
wherein the mechanically coupling includes placing at least part of the chip in the at least a recess; and
wherein the mechanically coupling also includes capacitively coupling the interposer leads and the antenna.
21. The method of claim 20 , wherein the forming the at least a recess includes forming a recess in the antenna substrate that leaves a thinned portion of the antenna substrate beneath the recess.
22. The method of claim 21 , wherein the mechanically coupling includes sealing the chip between the interposer substrate and the thinned portion of the antenna substrate.
23. The method of claim 20 , wherein the forming the at least a recess includes forming a hole in the antenna substrate.
24. The method of claim 23 , wherein the forming the hole includes punching out a portion of the antenna substrate.
25. The method of claim 23 , wherein the mechanically coupling includes passing at least a portion of the chip fully Through the hole.