Method for aligning a cassette pod to an overhead hoist transport system

• US 6,453,574 B1
• Filed: 03/28/2001
• Issued: 09/24/2002
• Est. Priority Date: 03/28/2001
• Status: Active Grant

• Current Assignee: Taiwan Semiconductor Manufacturing Company Limited
• Original Assignee: Taiwan Semiconductor Manufacturing Company Limited
• Inventors: Chen, Raymond
• Primary Examiner(s): Gutierrez, Diego
• Assistant Examiner(s): REIS, TRAVIS M
• Application Number:
  US09/820,129
• Publication Number:
  US 20020139001A1
• Time in Patent Office: 545 Days
• Field of Search: 33/1.LE, 333/01, 333/91, 333/92, 334/13, 335/20, 335/33, 336/13, 336/44, 336/45
• US Class Current: 33/645
• CPC Class Codes: H01L 21/67775 Docking arrangements
• CPC Class Codes: H01L 21/68 for positioning, orientation or alignment

Abstract

A method for aligning a cassette pod on the loadport of a process machine to an overhead hoist transport (OHT) system is disclosed. The method can be carried out by marking a first standard reference line on a clean room floor to which the OHT system is aligned, followed by aligning two plumb bobs at two points that are at least 5 cm apart to the first standard reference line on the floor with tips of the plumb bobs suspended over and positioned juxtaposed to the floor. A second standard reference line is then formed by interconnecting the two plumb bobs at an elevation above a top surface of the cassette pod, followed by aligning a center line of the cassette pod to the second standard reference line. The present invention novel method can therefore be executed utilizing simple mechanical equipment without the need of a sophisticated laser alignment system.

Claims

1. A method for aligning a cassette pod on the loadport of a process machine to an overhead hoist transport (OHT) system comprising the steps of:

marking a first standard reference line on a floor to which said OHT system is aligned;

aligning two plumb bobs at two points that are at least 5 cm apart to said first standard reference line on said floor with tips of said two plumb bobs suspended over and juxtaposed to said floor;

marking a second standard reference line by interconnecting said two plumb bobs at an elevation above said cassette pod; and

aligning a center line of said cassette pod to said second standard reference line.

2. A method for aligning a cassette pod on the loadport of a process machine to an overhead hoist transport system according to claim 1 further comprising the step of providing said two plumb bobs that are connected by a string.

3. A method for aligning a cassette pod on the loadport of a process machine to an overhead hoist transport system according to claim 1 further comprising the step of marking said second standard reference line at an elevation above and juxtaposed to a top surface of said cassette pod.

4. A method for aligning a cassette pod on the loadport of a process machine to an overhead hoist transport system according to claim 1 further comprising the step of marking two center lines perpendicular to and intersecting each other on a top surface of said cassette pod and forming a center point.

5. A method for aligning a cassette pod on the loadport of a process machine to an overhead hoist transport system according to claim 4 further comprising the step of aligning said center point to said second standard reference line.

6. A method for aligning a cassette pod on the loadport of a process machine to an overhead hoist transport system according to claim 1 further comprising the step of aligning two plumb bobs at two points that are at least 10 cm apart.

7. A method for aligning a cassette pod on the loadport of a process machine to an overhead hoist transport system according to claim 1 further comprising the step of aligning two plumb bobs at two points that are apart by a distance that is at least a width of said process machine.

8. A method for aligning a cassette pod on the loadport of a process machine to an overhead hoist transport system according to claim 1 further comprising the step of marking said first standard reference line on a raised floor panel situated in a clean room.

9. A method for aligning a cassette pod on the loadport of a process machine to an overhead hoist transport system according to claim 1 further comprising the step of providing said cassette pod in a front opening unified pod (FOUP).

10. A method for aligning a cassette pod on the loadport of a process machine to an overhead hoist transport (OHT) system comprising the steps of:

marking a first standard reference line on a floor to which said OHT system is aligned;

providing two plumb bobs that are interconnected by a string, each at one of the two free ends of the string;

aligning said two plumb bobs at two points that are at least 5 cm apart to said first standard reference line on said floor with tips of said two plumb bobs suspended over and positioned juxtaposed to said floor and with said string positioned over said cassette pod;

marking a second standard reference line along said string; and

aligning a center line of said cassette pod to said second standard reference line.

11. A method for aligning a cassette pod on the loadport of a process machine to an overhead hoist transport system according to claim 10 further comprising the step of marking said second standard reference line at an elevation above and juxtaposed to a top surface of said cassette pod.

12. A method for aligning a cassette pod on the loadport of a process machine to an overhead hoist transport system according to claim 10 further comprising the step of marking two center lines perpendicular to and intersecting each other on a top surface of said cassette pod and forming a center point.

13. A method for aligning a cassette pod on the loadport of a process machine to an overhead hoist transport system according to claim 12 further comprising the step of aligning said center point to said second standard reference line.

14. A method for aligning a cassette pod on the loadport of a process machine to an overhead hoist transport system according to claim 10 further comprising the step of aligning said two plumb bobs at two points that are at least 10 cm apart.

15. A method for aligning a cassette pod on the loadport of a process machine to an overhead hoist transport system according to claim 10 further comprising the step of aligning said two plumb bobs at two points that are apart by a distance that is at least a width of said process machine.

16. A method for aligning a cassette pod on the loadport of a process machine to an overhead hoist transport system according to claim 10 further comprising the step of marking said first standard reference line on a raised floor panel situated in a clean room.

17. A method for aligning a cassette pod on the loadport of a press machine to an overhead hoist transport system according to claim 10 further comprising the step of providing said cassette pod in a front opening unified pod (FOUP).