Endpoint detector for a semiconductor processing station and associated methods

1. A semiconductor processing apparatus comprising:

a semiconductor processing station for a semiconductor wafer comprising a substrate and at least one layer thereon to be processed; and

an endpoint detector associated with said semiconductor processing station and comprising

a non-contact probe configured to probe the semiconductor wafer,

an optical transmitter configured to transmit an optical signal to said non-contact probe,

an optical receiver configured to receive a reflected optical signal from said non-contact probe, and

a controller configured to generate a surface potential profile of the at least one layer based on the reflected optical signal to control said semiconductor processing station.

2. The semiconductor processing apparatus according to claim 1 , wherein said controller comprises a memory configured to store a plurality of surface potential profiles corresponding to a plurality of different type processed layers, and said controller being further configured to control said semiconductor processing station based on comparing the generated surface potential profile to the stored plurality of surface potential profiles.

3. The semiconductor processing apparatus according to claim 1 , wherein said controller is further configured to generate a height profile of the at least one layer based on the reflected optical signal to control said semiconductor processing station.

4. The semiconductor processing apparatus according to claim 3 , wherein said controller comprises a memory configured to store a plurality of height profiles corresponding to a plurality of different type processed layers, and said controller being further configured to control said semiconductor processing station based on comparing the generated height profile to the stored plurality of height profiles.

5. The semiconductor processing apparatus according to claim 1 , wherein said non-contact probe comprises a Kelvin probe.

6. The semiconductor processing apparatus according to claim 3 , wherein the reflected optical signal comprises a first waveform component corresponding to the surface potential profile, and a second waveform component different from the first waveform component corresponding to the height profile; and wherein said controller is further configured to process the first and second waveform components.

7. The semiconductor processing apparatus according to claim 1 , wherein said semiconductor processing station comprises a chemical-mechanical polishing (CMP) station.

8. The semiconductor processing apparatus according to claim 7 , wherein said CMP station comprises a rotatable polishing table and a window embedded therein; and wherein said non-contact probe is positioned adjacent the window.

9. The semiconductor processing apparatus according to claim 8 , wherein said window has an upper surface that is substantially coplanar with an upper surface of said table.

10. The semiconductor processing apparatus according to claim 8 , wherein said window comprises at least one of quartz, fused silica, sapphire and diamond.

11. An endpoint detector for a semiconductor processing station comprising:

a non-contact probe configured to probe a semiconductor wafer to be processed by the semiconductor processing station, the semiconductor wafer comprising a substrate and at least one layer thereon to be processed;

an optical transmitter configured to transmit an optical signal to said non-contact probe;

an optical receiver configured to receive a reflected optical signal from said non-contact probe; and

a controller configured to generate a surface potential profile of the at least one layer based on the reflected optical signal to control the semiconductor processing station.

12. The endpoint detector according to claim 11 wherein said controller comprises a memory configured to store a plurality of surface potential profiles corresponding to a plurality of different type processed layers, and said controller being further configured to control the semiconductor processing station based on comparing the generated surface potential profile to the stored plurality of surface potential profiles.

13. The endpoint detector according to claim 11 , wherein said controller is further configured to generate a height profile of the at least one layer based on the reflected optical signal to control said semiconductor processing station.

14. The endpoint detector according to claim 13 , wherein said controller comprises a memory configured to store a plurality of height profiles corresponding to a plurality of different type processed layers, and said controller being further configured to control the semiconductor processing station based on comparing the generated height profile to the stored plurality of height profiles.

15. The endpoint detector according to claim 11 , wherein said non-contact probe comprises a Kelvin probe.

16. The endpoint detector according to claim 11 , wherein the semiconductor processing station comprises a chemical-mechanical polishing (CMP) station.

17. A method for operating a semiconductor processing apparatus comprising a semiconductor processing station for a semiconductor wafer comprising a substrate and at least one layer thereon to be processed, and an endpoint detector associated with the semiconductor processing station, the endpoint detector comprising a non-contact probe, an optical transmitter, an optical receiver, and a controller, the method comprising:

positioning the non-contact probe adjacent the semiconductor wafer;

operating the optical transmitter to transmit an optical signal to the non-contact probe;

operating the optical receiver to receive a reflected optical signal from the non-contact probe; and

operating the controller to generate a surface potential profile of the at least one layer based on the reflected optical signal to control the semiconductor processing station.

18. The method according to claim 17 , wherein operating the controller further comprises controlling the semiconductor processing station based on comparing the generated surface potential profile to the stored plurality of surface potential profiles.

19. The method according to claim 17 , wherein operating the controller further comprises generating a height profile of the at least one layer based on the reflected optical signal to control the semiconductor processing station.

20. The method according to claim 19 , wherein operating the controller further comprises controlling the semiconductor processing station based on comparing the generated height profile to the stored plurality of height profiles.

21. The method according to claim 17 , wherein the non-contact probe comprises a Kelvin probe.

22. The method according to claim 19 , wherein the reflected optical signal comprises a first waveform component corresponding to the surface potential profile, and a second waveform component different from the first waveform component corresponding to the height profile; and wherein operating the controller further comprises processing the first and second waveform components.

23. The method according to claim 17 , wherein the semiconductor processing station comprises a chemical-mechanical polishing (CMP) station.

24. A semiconductor processing apparatus comprising:

a semiconductor processing station for a semiconductor wafer comprising a substrate and at least one layer thereon to be processed; and

an endpoint detector associated with said semiconductor processing station and comprising

a non-contact probe configured to probe the semiconductor wafer,

an optical transmitter configured to transmit an optical signal to said non-contact probe,

an optical receiver configured to receive a reflected optical signal from said non-contact probe, and

a controller configured to generate a height profile of the at least one layer based on the reflected optical signal to control said semiconductor processing station.

25. The semiconductor processing apparatus according to claim 24 , wherein said controller comprises a memory configured to store a plurality of height profiles corresponding to a plurality of different type processed layers, and said controller being further configured to control said semiconductor processing station based on comparing the generated height profile to the stored plurality of height profiles.

26. The semiconductor processing apparatus according to claim 24 , wherein said non-contact probe comprises a Kelvin probe.

27. The semiconductor processing apparatus according to claim 24 , wherein said semiconductor processing station comprises a chemical-mechanical polishing (CMP) station.

28. An endpoint detector for a semiconductor processing station comprising:

a non-contact probe configured to probe a semiconductor wafer to be processed by the semiconductor processing station, the semiconductor wafer comprising a substrate and at least one layer thereon to be processed;

an optical transmitter configured to transmit an optical signal to said non-contact probe;

an optical receiver configured to receive a reflected optical signal from said non-contact probe; and

a controller configured to generate a height profile of the at least one layer based on the reflected optical signal to control the semiconductor processing station.

29. The endpoint detector according to claim 28 , wherein said controller comprises a memory configured to store a plurality of height profiles corresponding to a plurality of different type processed layers, and said controller being further configured to control the semiconductor processing station based on comparing the generated height profile to the stored plurality of height profiles.

30. The endpoint detector according to claim 28 , wherein said non-contact probe comprises a Kelvin probe.

31. The endpoint detector according to claim 28 , wherein the semiconductor processing station comprises a chemical-mechanical polishing (CMP) station.