Wafer aligner

1. A semiconductor wafer transport apparatus comprising:

a frame;

a transport arm movably mounted to the frame and having at least one end effector movably mounted to the arm so that the at least one end effector traverses, with the arm as a unit, in a first direction relative to the frame, and traverses linearly, relative to a portion of the transport arm adjacent the end effector, in a second direction; and

an edge detection sensor mounted to the transport arm so that the edge detection sensor moves with the transport arm as a unit relative to the frame, the edge detection sensor being a common sensor effecting edge detection of each wafer of more than one wafers simultaneously supported by the at least one end effector;

wherein the edge detection sensor is configured so that the edge detection of each wafer is effected by and coincident with the traverse in the second direction of each end effector of the at least one end effector on the transport arm.

2. The semiconductor wafer transport apparatus of claim 1 , wherein the traverse of each end effector in the second direction linearly transports a corresponding wafer, seated on the end effector, of the more than one wafers simultaneously supported by the at least one end effector, relative to the edge detection sensor effecting edge detection.

3. The semiconductor wafer transport apparatus of claim 2 , wherein the edge detection sensor is configured to detect an edge of the wafer and identify therefrom a wafer location and misalignment with respect to a predetermined reference frame.

4. The semiconductor wafer transport apparatus of claim 2 , further comprising a wafer aligner mounted to the transport arm so that the aligner and the transport arm move as a unit relative to the frame, the aligner being disposed to cooperate with each end effector and effect wafer alignment of the corresponding wafer seated on the end effector.

5. The semiconductor wafer transport apparatus of claim 2 , further comprising a controller configured to cycle a linear traverse of each end effector past the edge detection sensor and effect edge detection of each corresponding wafer.

6. The semiconductor wafer transport apparatus of claim 5 , wherein the controller is configured to sequentially cycle the linear traverse of all end effectors before engaging a first wafer with a wafer aligner mounted to the transport arm.

7. The semiconductor wafer transport apparatus of claim 1 , wherein each end effector has an independent drive configured so that each end effector has independent linear traverse in the second direction.

8. The semiconductor wafer transport apparatus of claim 1 , wherein the at least one end effector includes a first end effector and a second end effector, each being independently driven relative to the transport arm.

9. The semiconductor wafer transport apparatus of claim 1 , wherein the edge detection is an on the fly edge detection.

10. A wafer processing apparatus comprising an enclosure with a load port and the transport apparatus as in claim 1 .

11. A semiconductor wafer transport apparatus comprising:

a frame;

a transport arm movably mounted to the frame and having a first end effector and a second end effector movably mounted to the arm so that

the first end effector and second end effector traverse, with the arm as a unit, in a first direction relative to the frame, and,

the first end effector and second end effector are independently driven for independent linear traverse, relative to a portion of the transport arm adjacent the end effector, in a second direction different from the first direction; and

an edge detection sensor mounted to the transport arm so that the edge detection sensor moves with the transport arm as a unit relative to the frame, the edge detection sensor being a common sensor effecting edge detection of each wafer of more than one wafers simultaneously supported by the first end effector and second end effector;

wherein the edge detection sensor is configured so that the edge detection of each wafer is effected by and coincident with the traverse in the second direction of each end effector of the first end effector and second end effector on the transport arm.

12. The semiconductor wafer transport apparatus of claim 11 , wherein the traverse of each end effector in the second direction linearly transports a corresponding wafer, seated on a respective end effector, of the more than one wafers simultaneously supported by the first end effector and the second end effector, relative to the edge detection sensor effecting edge detection.

13. The semiconductor wafer transport apparatus of claim 12 , wherein the edge detection sensor is configured to detect an edge of the wafer and identify therefrom a wafer location and misalignment with respect to a predetermined reference frame.

14. The semiconductor wafer transport apparatus of claim 12 , further comprising a wafer aligner mounted to the transport arm so that the aligner and the transport arm move as a unit relative to the frame, the aligner being disposed to cooperate with each end effector and effect wafer alignment of the corresponding wafer seated on a respective one of the first end effector and the second end effector.

15. The semiconductor wafer transport apparatus of claim 12 , further comprising a controller configured to cycle a linear traverse of each end effector past the edge detection sensor and effect edge detection of each corresponding wafer.

16. The semiconductor wafer transport apparatus of claim 15 , wherein the controller is configured to sequentially cycle the linear traverse of all end effectors before engaging a first wafer with a wafer aligner mounted to the transport arm.

17. The semiconductor wafer transport apparatus of claim 11 , wherein each end effector has an independent drive configured to effect the independent linear traverse of each end effector in the second direction.

18. A wafer processing apparatus comprising an enclosure with a load port and the transport apparatus as in claim 11 .

19. The wafer processing apparatus of claim 11 , wherein the edge detection is an on the fly edge detection.