Vacuum chamber load lock structure and article transport mechanism
View Patent ↗A vacuum chamber used for processing articles, such as integrated circuit wafers, display panels, and the like, has a small load lock chamber formed at an opening in a wall of the chamber by a moveable article supporting surface within the chamber and a cover outside of the chamber. The supporting surface and cover are sealed to the chamber wall when urged against it. Articles placed into the load lock chamber, when the cover is opened, are moved into the vacuum chamber for processing by moving the supporting surface away from the wall after the cover has been closed and a vacuum established in the load lock chamber. Articles are removed from the vacuum chamber in a reverse manner. Various mechanisms are describe for moving the articles, including a particular robotic device that simultaneously swaps the positions of two articles between the supporting surface and a processing location within the vacuum chamber by first pulling the articles together and then rotating them in a half-circle. Integrated circuit wafers are preferably carried on a domed surface formed of wedge shaped pieces fit together on a frame, where the wedge shaped pieces and their wafers are individually removable from the frame for transfer to another frame at a different location.
1. A method of processing articles within a vacuum chamber and moving the articles between the vacuum chamber and the outside through a load lock chamber, during sequential time intervals, comprising:
during a first time interval, opening the load lock chamber to the outside while remaining closed to the vacuum chamber, simultaneously removing a previously processed first batch of one or more articles from the load lock chamber to the outside and loading a second batch of one or more articles from the outside into the load lock chamber, while a third batch of one or more articles is being processed in the vacuum chamber,
during a second time interval, closing the load lock chamber to the outside, reducing the pressure within the load lock chamber to substantially that of the vacuum chamber, and opening the load lock chamber to the vacuum chamber, while the third batch of one or more articles is being processed in the vacuum chamber,
during a third time interval, simultaneously moving the second batch of one or more articles from the load lock chamber to the vacuum chamber and moving the third batch of one or more articles from the vacuum chamber to the load lock chamber,
during a fourth time interval, closing the load lock chamber from the vacuum chamber and then venting the load lock chamber to the outside, while the second batch of one or more articles is being processed in the vacuum chamber, and
during a fifth time interval, opening the load lock chamber to the outside while remaining closed to the vacuum chamber, simultaneously removing the third batch of one or more articles from the load lock chamber to the outside and loading a fourth batch of one or more articles from the outside into the load lock chamber, while the second batch of one or more articles is being processed in the vacuum chamber,
wherein moving and processing the first, second, third and fourth batches of one or more articles includes moving a domed surface carrying a plurality of integrated circuit wafers and processing said integrated circuit wafers, and
wherein the domed surface is formed of a plurality of wedge shaped pieces that are removeably placed together on a frame, and each of the moving and removing of a domed surface includes sequentially moving one of the wedge shaped pieces at a time.
2. A method of moving a plurality of integrated circuit wafers from one location to another location, comprising: positioning the plurality of wafers across a plurality of wedge shaped pieces that are fit together on a first frame to form a domed surface, moving one of the wedge shaped pieces at a time from the first frame to a second frame until all of said plurality of wedge shaped pieces are moved from the first frame to the second frame.