Air bearing compatible with operation in a vacuum
AssigneeNikon Corporation
InventorMichael Sogard
Life of this patent
Estimating the term…
Abstract
Methods and apparatus for enabling the stroke length of a linear guide that is suitable for use in an environment with high vacuum levels to be substantially independent of a length associated with the linear guide are disclosed. According to one aspect of the present invention, a guide bearing system includes a linear guide and a first guide beam. The linear guide has an inner surface which includes an air pad. The linear guide is wrapped around the first guide beam such that it may slide with respect to the guide beam. The guide beam includes a first chamber that is in fluid communication with the linear guide through at least one of a first plurality of ports in the guide beam which enable access to the first chamber.
Claims39
A guide bearing system, the guide bearing system comprising:
- a linear guide, the linear guide having an inner surface which includes an air pad;
- and
- a first guide beam, the linear guide being arranged to substantially wrap around the first guide beam and to slide with respect to the guide beam, the guide beam including a first chamber, the first chamber being in fluid communication with the linear guide through at least one of a first plurality of ports in the guide beam which enable access to the first chamber.
A guide bearing system, the guide bearing system comprising:
- a linear guide, the linear guide including an inner surface which includes an air pad;
- and
- a first guide beam, the linear guide being arranged to substantially wrap around the first guide beam and to slide with respect to the guide beam, the guide beam including a first chamber with a first port, wherein the first port includes a first sealing arrangement that is arranged to control access to the first chamber, the first chamber being in fluid communication with the linear guide through the first port when the first sealing arrangement is arranged to enable access to the first chamber.
A method for scanning a stage, the stage being coupled to an air bearing linear guide, the air bearing linear guide being arranged to slide over a guide beam, wherein the guide beam includes an internal chamber with at least a first exhaust port and a second exhaust port on a first side, the method comprising:
- sliding the air bearing linear guide to overlap the first exhaust port;
- maintaining the first exhaust port in a substantially open configuration when the air bearing linear guide overlaps the first exhaust port, wherein the open configuration is arranged to enable fluid communication between the air bearing linear guide and the internal chamber;
- and
- maintaining the second exhaust port in a substantially closed configuration when the air bearing linear guide does not overlap the second exhaust port, wherein the closed configuration is arranged to substantially minimize fluid communication with the internal chamber through the second exhaust port.
Dependencies are inferred from the claim text.