Remote wafer presence detection with passive RFID

1. A system for remotely detecting the presence of a wafer comprising:

a passive RFID circuit, wherein the RFID circuit is operably coupled to a wafer gripper located at an end of a transfer arm located inside a vacuum chamber of an ion implantation system;

a reader located outside the vacuum chamber and configured to transmit wirelessly an interrogation signal to the passive RFID circuit; and

wherein the passive RFID circuit provides an indication relating to whether or not a wafer is secured by the wafer gripper in response to the interrogation signal.

2. The system for remotely detecting the presence of a wafer of claim 1 , wherein the reader generates an RF interrogation signal.

3. The system for remotely detecting the presence of a wafer of claim 1 , wherein the passive RFID circuit comprises: wiring, a passive RFID tag and a micro-switch, wherein the wiring electrically connects together the passive RFID tag and the micro-switch, and wherein the micro-switch is configured to close and alter a response of the passive RFID tag in response to the interrogation signal when the wafer is secured by the wafer gripper.

4. The system for remotely detecting the presence of a wafer of claim 3 , wherein the passive RFID circuit transmits a response signal when activated by the interrogation signal transmitted by the reader when the micro-switch is open in the circuit when a wafer is not present at the wafer gripper.

5. The system for remotely detecting the presence of a wafer of claim 1 , further comprising a controller and a power supply coupled to the reader, wherein the controller detects the presence of the wafer based upon a response signal generated by the passive RFID circuit in response to the interrogation signal.

6. The system for remotely detecting the presence of a wafer of claim 1 , wherein the ion implantation system comprises an equipment front end module, the vacuum chamber, a load lock and the transfer arm.

7. The system for remotely detecting the presence of a wafer of claim 5 , wherein the controller obtains wafer presence information from the response signal and selects a mode of operation of the ion implantation system according to the wafer presence information.

8. The system for remotely detecting the presence of a wafer of claim 1 , wherein the response signal comprises tag information, force information, or position information.

9. A method of detecting wafer presence within a system comprising:

delivering a wafer to a load lock in an ion implantation system;

gripping the wafer with a transfer arm;

generating a first signal in a passive RFID tag induced by a reader component indicating the gripping of the wafer;

moving the wafer to a chuck if the first signal is generated;

generating a second signal in the passive RFID tag induced by the reader component indicating proximity to the chuck upon moving the wafer to the chuck;

clamping the wafer to the chuck if the second signal is generated; and

releasing the wafer from the transfer arm after clamping the wafer to the chuck.

10. The method of claim 9 , wherein the reader generates an RF signal.

11. The method of claim 9 , wherein the passive RFID tag comprises an antenna coil, a microprocessor and a substrate.

12. The method of claim 9 , wherein the reader component is located outside the ion implantation system vacuum chamber.

13. The method of claim 9 , wherein the transfer arm with an attached passive RFID tag is located inside the vacuum chamber.

14. The method of claim 9 , wherein the ion implantation system comprises an equipment front end module, a vacuum chamber, a load lock and a transfer arm.

15. A remote wafer detection system, comprising:

a passive RFID circuit, wherein the RFID circuit is operably coupled to a wafer gripper located at an end of a transfer arm located inside a vacuum chamber of an ion implantation system;

a reader located outside the vacuum chamber and configured to transmit wirelessly an interrogation signal to the passive RFID circuit; and

wherein the passive RFID circuit provides a response signal related to whether or not a wafer is properly gripped by the wafer gripper in response to the interrogation signal.

16. The system of claim 15 , wherein the reader generates an RF interrogation signal.

17. The system of claim 15 , wherein the passive RFID circuit comprises: wiring, a passive RFID tag and a micro-switch, wherein the wiring electrically connects together the passive RFID tag and the micro-switch, and wherein the micro-switch is configured to close and alter a response of the passive RFID tag in response to the interrogation signal when the wafer is gripped by the wafer gripper.

18. The system of claim 15 , wherein the passive RFID circuit transmits the response signal when activated by the interrogation signal transmitted by the reader when a micro-switch is open in the circuit when a wafer is not present.

19. The system of claim 15 , wherein the passive RFID circuit is inactivated when a micro-switch is closed by gripping of the wafer.

20. The system of claim 15 , further comprising a controller and a power supply coupled to the reader, wherein the controller remotely detects the presence of a wafer based upon the response signal generated by the passive RFID circuit.

21. The system of claim 15 , wherein the ion implantation system of comprises an equipment front end module, the vacuum chamber, a load lock and the transfer arm.

22. The system of claim 20 , wherein the controller obtains wafer presence information from the response signal and selects a mode of operation of the ion implantation system according to the wafer presence information.

23. The system of claim 15 , wherein the response signal comprises tag information, force information, or position information.

24. The method of claim 9 , further comprising:

opening and closing the transfer arm if the first signal is not generated.

25. The method of claim 9 , further comprising:

alerting an operator if the second signal is not generated.