Wafer center finding with charge-coupled devices
View Patent ↗A device having a robotic arm within a robot chamber. The robotic arm includes an end effector adapted to handle a wafer. A linear array of charge-coupled devices are provided within the interior of the robot chamber, the linear array positioned to acquire image data from a measurement volume in one or more predetermined locations within the robot chamber.
1. A device comprising:
a robotic arm within a robot chamber, the robotic arm including an end effector adapted to handle a wafer; and
a linear array of charge-coupled devices within the interior of the robot chamber,
the linear array positioned to acquire image data from a measurement volume in one or more predetermined locations within the robot chamber;
wherein, the linear array of charge-coupled devices is coupled to the robotic arm and configured so that edge data, captured by the linear array of charge coupled devices, of the wafer resting on the end effector and a transport path of the wafer transported by the robotic arm within the measurement volume define a predetermined position of the wafer in the measurement volume.
2. The device of claim 1 further comprising an external illumination source that illuminates the linear array.
3. The device of claim 1 further comprising a wireless power coupling that inductively powers the linear array.
4. The device of claim 1 further comprising a wireless transceiver for exchanging data wirelessly with the linear array.
5. The device of claim 4 wherein the wireless transceiver is positioned outside the robotic chamber.
6. The device of claim 4 wherein the data includes the image data.
7. The device of claim 1 wherein the linear array is a 1 by n array of charge-coupled devices.
8. The device of claim 1 wherein the linear array includes a two dimensional array of charge-coupled devices.
9. The device of claim 1 further comprising a plurality of linear arrays each capturing image data at a different location within the interior.
10. The device of claim 1 wherein the robotic arm includes a chuck on the end effector adapted to rotate the wafer within the measurement volume of the linear array.
11. The device of claim 10 wherein the robotic arm is adapted to lift the wafer into the measurement volume of the linear array.
12. The device of claim 10 wherein the chuck rotates between one-hundred eighty degrees and three-hundred sixty degrees.
13. The device of claim 1 further comprising a rotating chuck adapted to lift the wafer from the end effector into the measurement volume of the linear array.
14. The device of claim 1 further comprising a processor configured to determine a center of the wafer using the image data.
15. The device of claim 1 further comprising a processor configured to determine a radius of the wafer using the image data.
16. The device of claim 1 further comprising a processor configured to identify an alignment notch on the wafer using the image data.
17. A device comprising:
a robotic arm within a robot chamber, the robotic arm including an end effector adapted to handle a wafer; and a linear array of charge-coupled devices on the end effector positioned to capture edge data from a wafer resting on the end effector, and a transport path of the wafer transported by the robotic arm within the measurement volume defines a predetermined position of the wafer in the measurement volume.
18. The device of claim 17 further comprising an external illumination source that illuminates the linear array.
19. The device of claim 17 further comprising a wireless power coupling that inductively powers the linear array.
20. The device of claim 17 further comprising a wireless transceiver for exchanging data wirelessly with the linear array.
21. The device of claim 20 wherein the wireless transceiver is positioned outside the robotic chamber.
22. The device of claim 17 wherein the linear array is a 1 by n array of charge-coupled devices.
23. The device of claim 17 wherein the linear array includes a two dimensional array of charge-coupled devices.
24. The device of claim 17 wherein the robotic arm includes a chuck on the end effector adapted to rotate the wafer within the measurement volume of the linear array.
25. The device of claim 17 further comprising a rotating chuck adapted to lift the wafer from the end effector and rotate the wafer within the measurement volume of the linear array.
26. The device of claim 17 further comprising a processor configured to determine a center of the wafer using the edge data.
27. The device of claim 17 further comprising a processor configured to determine a radius of the wafer using the edge data.
28. The device of claim 17 further comprising a plurality of linear arrays positioned to capture edge data from a number of locations on a surface of the end effector.