Method and apparatus for controlling droplet in extreme ultraviolet light source
AssigneeTaiwan Semiconductor Manufacturing Company, Ltd.
InventorsChi-Hung Liao, Yueh-Lin Yang
Life of this patent
Estimating the term…
Abstract
A lithography method in semiconductor fabrication is provided. The method includes generating multiple groups of small drops of a target material through a number of nozzles in such a way that small drops in each of the groups are aggregated to an elongated droplet of the target material. The method also includes generating a laser pulse from a laser generator to convert the elongated droplets to plasma which generates an EUV radiation. The method further includes exposing a semiconductor wafer to the EUV radiation.
Claims20
A lithography method in semiconductor fabrication, comprising:
- generating multiple groups of small drops of a target material through a plurality of nozzles in such a way that the small drops in each of the groups are aggregated to an elongated droplet of the target material;
- generating a laser pulse from a laser generator to convert the elongated droplets to plasma which generates an EUV radiation;
- exposing a semiconductor wafer to the EUV radiation;
- performing a measurement process to measure a condition of a first one of the elongated droplets aggregated from a first group of small drops or the EUV radiation irradiated by the first one of the elongated droplets;
- and
- selecting the nozzles for generating a second one of the elongated droplets according to a result of the measurement process.
A lithography method in semiconductor fabrication, comprising:
- generating a plurality of elongated droplets of a target material along a first axis from a droplet generator, wherein each of the elongated droplets has a longitudinal axis that is oblique with the first axis and has a length in the longitudinal axis greater than its width perpendicular to the longitudinal axis, wherein each of the elongated droplets is aggregated by a plurality of small drops of the target material that are generated from a plurality of nozzles of the droplet generator, the small drops of the target material are generated by the nozzles that are separated from one another by a distance, and a ratio of the distance and a width of one of the nozzles is in a range from about 0 to about 1;
- generating a laser pulse from a laser generator to convert the elongated droplets to plasma which generates an EUV radiation;
- and
- exposing a semiconductor wafer to the EUV radiation.
A lithography exposure system, comprising:
- a droplet generator configured to generate a plurality of elongated droplets of a target material and comprising:
- a reservoir for storing the target material;
- and
- a plurality of nozzles fluidly connected to the reservoir, wherein the nozzles are arranged such that small drops of the target material from different nozzles are aggregated to one of the elongated droplets, wherein the nozzles have central longitudinal axes that are substantially parallel and that are spaced apart in a direction substantially perpendicular to an extension direction of the central longitudinal axes of the nozzles;
- a laser generator configured to generate a laser pulse to convert the elongated droplets to plasma which generates a EUV radiation;
- and
- a collector mirror configured to reflect the EUV radiation.
Dependencies are inferred from the claim text.