Reticle storage system

• US 6,690,993 B2
• Filed: 06/27/2001
• Issued: 02/10/2004
• Est. Priority Date: 10/12/2000
• Status: Expired due to Term

• Current Assignee: Brooks Automation Ltd. (United Kingdom) (Azenta, Inc.)
• Original Assignee: R. Foulke Development Company, LLC
• Inventors: Lui, Takman, Ohlenbusch, Cord W., Foulke, Richard F., Foulke, Richard F. Jr.
• Primary Examiner(s): Tran, Khoi H.
• Application Number:
  US09/892,945
• Publication Number:
  US 20020044856A1
• Time in Patent Office: 958 Days
• Field of Search: 700/213, 700/214, 700/218, 700/245, 700/255, 700/258, 700/259, 700/262, 414/217, 414/217.1, 414/266, 414/267, 414/273, 414/274, 414/277, 414/279, 414/935, 414/937, 414/938, 414/939, 414/941
• US Class Current: 700/218
• CPC Class Codes: G03F 7/70741 Handling masks outside exposure position, e.g. reticle libraries
• CPC Class Codes: G03F 7/70866 of mask or workpiece
• CPC Class Codes: G03F 7/70916 Pollution mitigation, i.e. mitigating effect of contamination or debris, e.g. foil traps
• CPC Class Codes: Y10S 414/137 including means for charging or discharging wafer cassette
• CPC Class Codes: Y10S 414/138 Wafers positioned vertically within cassette
• CPC Class Codes: Y10S 414/139 including wafer charging or discharging means for vacuum chamber

Abstract

A reticle storage system includes a reticle rack having a series of lateral slots, each for storing a reticle. Access to the reticles is provided on a lateral side of the rack. The enclosure has a series of doors for providing access to the reticles in the slots. An air circulation system flows filtered air past the reticles in the rack to prevent contaminants from accumulating on the reticles. The air circulation system is capable of providing positive air pressure within the enclosure with one door open, thereby preventing contaminants from entering the enclosure through the open door.

Claims

1. A reticle storage system comprising:

a reticle rack in a linear row configuration having a series of lateral slots, each for storing a reticle, access to the reticles being provided on a lateral side of the rack;

an enclosure for housing the rack, the enclosure having a series of doors for providing access to the reticles in the slots;

an air circulation system for flowing filtered air past the reticles in the rack to prevent contaminants from accumulating on the reticles, the air circulation system capable of providing positive air pressure within the enclosure with one door open, thereby preventing contaminants from entering the enclosure through the open door;

a robot positioned within the enclosure for removing reticles from and replacing reticles in the reticle rack, the robot including a drive system for driving the robot; and

a controller for controlling the drive system of the robot, the controller calculating a profile of a commanded motion before said motion is performed, said motion being performed only when the controller determines that said motion is capable of being performed.

2. The system of claim 1 in which the controller recalculates said profile until the controller determines that said motion is capable of being performed.

3. The system of claim 1 in which the controller calculates said profile in sections.

4. The system of claim 1 in which the robot further includes a gripper arm for gripping the reticles, the gripper arm being driveable by a gripper arm drive away from and towards the reticle rack.

5. The system of claim 4 in which the robot has a vertical column to which the gripper arm is movably mounted, vertical movement of the gripper arm relative to the vertical column capable of being provided by a vertical drive.

6. The system of claim 5 in which the robot has a carriage to which the vertical column is rotatably mounted, rotary motion of the vertical column capable of being provided by a rotary drive.

7. The system of claim 5 in which the robot includes a gripper arm counter balance, the counter balance being housed within the vertical column to minimize particle generation and to be positioned near the center of mass of the robot.

8. The system of claim 6 in which the drive system includes a bottom drive for driving the carriage of the robot alongside the reticle rack.

9. The system of claim 4 further comprising a vision system for determining whether a slot in the reticle rack is occupied or empty, the position of the gripper relative to the slot, and whether the gripper is correctly gripping a reticle.

10. The system of claim 8 further comprising a pod opening system for placing and removing reticles from pods with the robot.

11. The system of claim 1 further comprising a manual tool for attaching to the reticle rack for removing and replacing reticles with minimal particle generation.

12. The system of claim 1 in which the enclosure includes a robot service location for servicing the robot, the robot service location capable of being isolated from the reticle rack to prevent contamination of the reticles during service of the robot.

13. A method of storing and managing reticles comprising:

storing reticles in lateral slots of a reticle rack in a linear row configuration, access to the reticles being provided on a lateral side of the rack;

housing the rack in an enclosure, the enclosure having a series of doors for providing access to the reticles in the slots;

flowing filtered air past the reticles in the rack with an air circulation system to prevent contaminants from accumulating on the reticles, the air circulation system capable of providing positive air pressure within the enclosure with one door open, thereby preventing contaminants from entering the enclosure through the open door;

removing reticles from and replacing reticles in the reticle rack with a robot positioned within the enclosure;

driving the robot with a drive system; and

calculating a profile of a commanded motion of the robot with a controller before said motion is performed, said motion being performed only when the controller determines that said motion is capable of being performed.

14. The method of claim 13 further comprising recalculating said profile until the controller determines that said motion is capable of being performed.

15. The method of claim 13 further comprising calculating said profile in sections.

16. The method of claim 13 further comprising providing the robot with a gripper arm for gripping the reticles, the gripper arm being driveable by a gripper arm drive away from and towards the reticle rack.

17. The method of claim 16 further comprising providing the robot with a vertical column to which the gripper arm is movably mounted, vertical movement of the gripper arm relative to the vertical column being provided by a vertical drive.

18. The method of claim 17 further comprising rotatably mounting the vertical column to a carriage, rotary motion of the vertical column being provided by a rotary drive.

19. The method of claim 18 further comprising driving the carriage alongside the reticle rack with a bottom drive.

20. The method of claim 16 further comprising determining with a vision system whether a slot in the reticle rack is occupied or empty, the position of the gripper relative to the slot, and whether the gripper is correctly gripping a reticle.

21. The method of claim 16 further comprising placing into and removing reticles from pods with the robot.

22. The method of claim 13 further comprising attaching a manual tool to the reticle rack for removing and replacing reticles with minimal particle generation.

23. The method of claim 13 further comprising providing a robot service location within the enclosure for servicing the robot, the robot service location capable of being isolated from the reticle rack to prevent contamination of the reticles during service of the robot.