Gas flushing system for use in lithographic apparatus
AssigneeASML Netherlands B.V.
InventorErik R. Loopstra
Life of this patent
Estimating the term…
Abstract
In a lithographic apparatus using exposure radiation of a relatively short wavelength, e.g. 157 or 126 nm, a laminar flow of N2 is provided across parts of the beam path in or adjacent to moving components of the apparatus. The laminar flow is faster than the maximum speed of the moving components and the diffusion rate of air thereby minimizing the contamination of the N2 by mixing with air. Laminar flow may be ensured by providing partitions to divide the beam path into separate spaces, by covering rough or non-planar surfaces in components on or adjacent to the laminar flow and by providing aerodynamic members.
Claims47
A lithographic projection apparatus comprising:
- a radiation system constructed and arranged to supply a projection beam of radiation;
- a first object table for holding a mask;
- a second object table for holding a substrate;
- a projection system constructed and arranged to image an irradiated portion of the mask onto a target portion of the substrate;
- and
- a gas structure constructed and arranged to supply a substantially laminar flow of flushing gas across at least a part of a path of said projection beam to displace ambient air therefrom, said flushing gas being substantially non-absorbent of said radiation,
- wherein said substantially laminar flow of flushing gas traverses a substantially non-obstructed region in said projection apparatus.
A method of manufacturing a device comprising:
- providing a substrate having a radiation-sensitive layer in a projection apparatus;
- irradiating portions of a mask bearing a pattern with a projection beam of radiation and imaging said irradiated portions of the mask onto target portions of said substrate;
- and
- providing flushing gas to flow in a substantially laminar flow across at least a part of a path of said projection beam to displace therefrom ambient air, said flushing gas being substantially non-absorbent of said radiation, and said laminar flow of flushing gas traversing a substantially non-obstructed region in said projection apparatus.
A lithographic projection apparatus comprising:
- a radiation system constructed and arranged to supply a projection beam of radiation;
- a first object table for holding a mask;
- a second object table for holding a substrate;
- a projection system constructed and arranged to image an irradiated portion of the mask onto a target portion of the substrate;
- and
- a gas structure constructed and arranged to supply a substantially laminar flow of flushing gas, in a vicinity of said first object table and said second object table, across at least a part of a path of said projection beam to displace ambient air therefrom, said flushing gas being substantially non-absorbent of said radiation.
A lithographic projection apparatus comprising:
- a radiation system constructed and arranged to supply a projection beam of radiation;
- a first object table for holding a mask;
- a second object table for holding a substrate;
- a projection system constructed and arranged to image an irradiated portion of the mask onto a target portion of the substrate;
- and
- a gas structure constructed and arranged to supply a substantially laminar flow of flushing gas, in a vicinity of said first object table, across at least a part of a path of said projection beam to displace ambient air therefrom, said flushing gas being substantially non-absorbent of said radiation.
A lithographic projection apparatus comprising:
- a radiation system constructed and arranged to supply a projection beam of radiation;
- a first object table for holding a mask;
- a second object table for holding a substrate;
- a projection system constructed and arranged to image an irradiated portion of the mask onto a target portion of the substrate;
- and
- a gas structure mounted to an extremity of at least one of said radiation system and said projection system, said gas structure is constructed and arranged to supply a laminar flow of flushing gas across at least a portion of a path of said projection beam, said flushing gas being substantially non-absorbent of said radiation.
Dependencies are inferred from the claim text.