Particle image velocimetry of extreme ultraviolet lithography systems
AssigneeTaiwan Semiconductor Manufacturing Company, Ltd.
InventorsEn Hao Lai, Chi Yang, Shang-Chieh Chien, Li-Jui Chen, Po-Chung Cheng
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Abstract
A method includes irradiating a target droplet in an extreme ultraviolet light source of an extreme ultraviolet lithography tool with light from a droplet illumination module. Light reflected and/or scattered by the target droplet is detected. Particle image velocimetry is performed to monitor one or more flow parameters inside the extreme ultraviolet light source.
Claims20
A method, comprising:
- irradiating a target droplet in an extreme ultraviolet (EUV) light source of an extreme ultraviolet lithography tool with non-ionizing light from a droplet illumination module;
- detecting light reflected and/or scattered by the target droplet;
- and
- performing particle image velocimetry, based on the detected light, to monitor one or more flow parameters inside the EUV light source.
A method, comprising:
- irradiating one or more of tin droplets and tin debris in an extreme ultraviolet light source of an extreme ultraviolet lithography tool with non-ionizing light from a droplet illumination module;
- detecting light reflected and/or scattered by the one or more of the tin droplets and the tin debris;
- and
- performing particle image velocimetry, based on the detected light, to monitor a rate of an amount of the tin droplets and the tin debris depositing on a collector mirror of the extreme ultraviolet light source.
An apparatus for monitoring flow parameters of particles in an extreme ultraviolet light source of an extreme ultraviolet lithography system, comprising:
- a droplet illumination module comprising a radiation source configured to illuminate a target droplet;
- a droplet detection module configured to detect light reflected and/or scattered by the target droplet;
- and
- a controller coupled to the droplet illumination module and the droplet detection module and configured to:
- perform particle image velocimetry to monitor one or more flow parameters inside the extreme ultraviolet light source.
Dependencies are inferred from the claim text.