Editing Immersion lithography (section)

==Throughput==
[[File:Immersion_tool_throughput.png|thumb|right|300px|'''Throughput of immersion lithography tools vs. dose.''' The throughput vs. dose is compared to for different pulse powers at the same slit width.]]

As of 1996, this was achieved through higher stage speeds,<ref name=stepscan>{{Cite web |url=https://staticwww.asml.com/doclib/productandservices/94081.pdf |title=M. A. van den Brink et al., Proc. SPIE 2726, 734 (1996). |access-date=2018-07-16 |archive-date=2017-08-09 |archive-url=https://web.archive.org/web/20170809032333/http://staticwww.asml.com/doclib/productandservices/94081.pdf |url-status=dead }}</ref><ref>I. Bouchoms et al., Proc. SPIE 8326, 83260L (2012)</ref> which in turn, as of 2013 were allowed by higher power [[Argon fluoride laser|ArF laser]] pulse sources.<ref>{{Cite web |vauthors=Rokitski R,Rafac  R,Dubi R,Thornes J,melchior J,Cacouris T,Haviland M,Brown  D, Cymer |date=2013 |title=120-W ArFi Laser Makes Higher-Dose Lithography Possible |url=https://www.photonics.com/Articles/120-W_ArFi_Laser_Makes_Higher-Dose_Lithography/a53765 |access-date=2022-11-09 |website=www.photonics.com}}</ref> Specifically, the throughput is directly proportional to stage speed V, which is related to dose D and rectangular slit width S and slit intensity I<sub>ss</sub> (which is directly related to pulse power) by V=I<sub>ss</sub>*S/D. The slit height is the same as the field height. The slit width S, in turn, is limited by the number of pulses to make the dose (n), divided by the frequency of the laser pulses (f), at the maximum scan speed V<sub>max</sub> by S=V<sub>max</sub>*n/f.<ref name=stepscan/> At a fixed frequency f and pulse number n, the slit width will be proportional to the maximum stage speed. Hence, throughput at a given dose is improved by increasing maximum stage speed as well as increasing pulse power.

According to ASML s product information about twinscan-nxt1980di, immersion lithography tools currently{{when|date=November 2022}} boasted the highest throughputs (275 WPH) as targeted for high volume manufacturing.<ref>{{Cite web |date=nd |title=The ASML NXT:1980Di lithography system |url=https://www.asml.com/en/products/duv-lithography-systems/twinscan-nxt1980di |access-date=2022-11-09 |website=www.asml.com |language=en}}</ref>