Substrate handling system for aligning and orienting substrates during a transfer operation

• US 20050265814A1
• Filed: 01/28/2005
• Published: 12/01/2005
• Est. Priority Date: 09/10/2003
• Status: Active Grant

• Current Assignee: Brooks Automation Ltd. (United Kingdom) (Azenta, Inc.)
• Original Assignee: Brooks Automation Incorporated (Azenta, Inc.)
• Inventors: Coady, Matthew W.
• Granted Patent: US 8,016,541 B2
• Time in Patent Office: Days
• US Class Current: 414/744.500
• CPC Class Codes: H01L 21/68 for positioning, orientation or alignment
• CPC Class Codes: H01L 21/68707 the wafers being placed on a robot blade, or gripped by a gripper for conveyance

Abstract

A system is provided for sensing, orienting, and transporting wafers in an automated wafer handling process that reduces the generation of particles and contamination so that the wafer yield is increased. The system includes a robotic arm for moving a wafer from one station to a destination station, and an end-effector connected to an end of the robotic arm for receiving the wafer. The end-effector includes a mechanism for gripping the wafer, a direct drive motor for rotating the wafer gripping mechanism, and at least one sensor for sensing the location and orientation of the wafer. A control processor is provided for calculating the location of the center and the notch of the wafer based on measurements by the sensor(s). Then, the control processor generates an alignment signal for rotating the wafer gripping mechanism so that the wafer is oriented at a predetermined position on the end-effector while the robotic arm is moving to another station.

Claims

1. A substrate transport apparatus comprising:

a movable transport arm; and

an end effector movably connected to the transport arm, the end effector having a chuck adapted for holding a substrate, and a motor for moving the substrate held by the chuck, wherein the motor is disposed relative to the chuck so that, when the substrate is held by the chuck, a center of the substrate is substantially co-incident with an axis of movement of the motor.

2. The apparatus according to claim 1, wherein the end effector has at least one sensor thereon to sense an predetermined characteristic of the substrate.

3. The apparatus according to claim 2, wherein the predetermined characteristic is at least one of an edge of the substrate or a fiducial feature of the substrate.

4. The apparatus according to claim 2, further comprising a controller in communication with the at least one sensor and the motor, and wherein the controller is programmed to actuate the motor for moving the substrate based on information from the at least one sensor.

5. The apparatus according to claim 4, wherein the controller is programmed to move the substrate with the motor substantially simultaneously with the transport arm moving the substrate from one station to another station.

6. The apparatus according to claim 1, wherein the end effector has a support member supporting the chuck, the chuck being rotatably mounted relative to the support member to rotate relative to the support member, and wherein the axis of movement is an axis of rotation of the motor.

7. The apparatus according to claim 1, wherein the chuck is adapted for edge gripping the substrate.

8. The apparatus according to claim 1, wherein the motor is a brushless motor and is located on a support member of the end effector supporting the chuck, the brushless motor being located on the support member at a location under the chuck.

9. The apparatus according to claim 8, further comprising a positional resolver connected to the chuck for providing position information of the chuck to a controller operating the motor.

10. The apparatus according to claim 1, wherein the motor comprises a stator and a rotor, the stator being integral to a base of the end effector, and the rotor being integral to the chuck.

11. A vacuum substrate processing system comprising the apparatus according to claim 1.

12. A substrate transport apparatus comprising:

a movable transport arm; and

an end effector movably connected to the transport arm and being adapted for holding a substrate thereon, the end effector comprising a PCB, the PCB forming at least part of a support member of the end effector for supporting the substrate when the substrate is held by the end effector.

13. The apparatus according to claim 12, wherein the PCB comprises at least part of a motor for moving the substrate on the end effector relative to the transport arm.

14. The apparatus according to claim 12, wherein a face of the PCB extends along at least a portion of a face of the substrate when the substrate is held by the end effector.

15. The apparatus according to claim 12, wherein the PCB has conductive traces formed therein defining windings for a motor stator.

16. The apparatus according to claim 15, wherein the motor stator is for a motor effecting movement of a chuck of the end effector.

17. The apparatus according to claim 12, wherein the end effector has a chuck for holding the substrate on the end effector, the chuck resting on the PCB.

18. The apparatus according to claim 12, wherein the end effector has at least one sensor thereon to sense an predetermined characteristic of the substrate.

19. The apparatus according to claim 18, wherein the PCB has integral windings formed therein defining at least a portion of a motor for moving the substrate on the end effector, and wherein the motor is operated by a controller using information from the at least one sensor.

20. A substrate transport apparatus comprising:

a movable transport arm;

an end effector movably connected to the transport arm, the end effector having-a base section mounting the end effector to the transport arm, and a chuck movably mounted to the base section and adapted for holding a substrate; and

a motor connected to the end effector for moving the substrate held by the chuck, wherein the motor is integral with the end effector, at least a drive part of the motor being mounted to the base section of the end effector and at least a reaction part of the motor being mounted to the chuck.

21. The apparatus according to claim 20, wherein the drive part is a stator and the reaction part is a rotor, and wherein the stator is disposed on the base section and the rotor on the chuck so that, when the substrate is held by the chuck, a center of the substrate is substantially co-incident with an axis of rotation of the motor.

22. The apparatus according to claim 20, wherein the motor is a brushless motor.

23. An end effector motor for an end effector of a substrate transport apparatus, the end effector having a support member and a chuck movably mounted to the support member and adapted for holding a substrate thereon, the motor comprising:

a stator sized and shaped for being embedded in the support member; and

a rotor operably interfacing with the stator and adapted to be mounted to the chuck of the end effector.

24. The motor according to claim 23, wherein the stator comprises windings formed on a PCB.

25. The motor according to claim 24, wherein the PCB is integral with the support member of the end effector.

26. The motor according to claim 23, wherein the rotor comprises at least one permanent magnet.

27. The motor according to claim 23, further comprising a rotary resolver connected to the rotor, and a controller communicably connected with the rotary resolver and the stator for commutating windings of the stator.

28. A substrate transport apparatus comprising:

a movable transport arm; and

an end effector movably connected to the transport arm, the end effector comprising a support member mounting the end effector to the transport arm, a chuck movably mounted to the support member and adapted for holding a substrate, and a motor for moving the substrate held by the chuck, wherein the support member has a portion of unitary construction that defines a stator of the motor.

29. The apparatus according to claim 28, wherein the chuck is mounted to the portion of unitary construction of the support member.

30. The apparatus according to claim 28, wherein the portion of unitary construction extends under the chuck.

31. The apparatus according to claim 28, wherein the motor comprises a rotor, the rotor being mounted to the chuck.

32. The apparatus according to claim 31, wherein the rotor comprises permanent magnets.

33. The apparatus according to claim 28, wherein the motor is a brushless motor.