Product IntroductionExcimer Laser Grade

Excimer Laser Grade
- CaF2 with High Optical Transmittance and Durability -

Manufacturing system of semiconductors support an information-oriented society. The key player, the semiconductor lithography equipment, uses extreme short wavelength vacuum ultraviolet lasers (ArF laser, KrF laser) to draw fine circuits. Since these lasers have a short wavelength and very high energy density, CaF2 with much higher laser durability is used rather than quartz.
We offer the excimer laser grade CaF2 product with high optical transmittance and durability as optical material for lasers, suitable for semiconductor lithography equipment.

Applications:
Semiconductor lithography equipment, window material for lasers in the ultraviolet region

* CaF2 products for the usual ultraviolet (UV) region are also available. Please feel free to inquire.

caf2

Refractive Index

Wavelength(nm)
(in a vacuum)
Refractive index for nitrogen
(22℃ 1013.25hPa)
780.237 1.430740
706.714 [r] 1.431662
656.454 [C] 1.432450
632.990 1.432877
587.725 [d] 1.433838
546.227 [e] 1.434926
468.269 [F] 1.437006
435.957 [g] 1.439460
404.770 [h] 1.441479
365.119 [i] 1.444880
334.224 1.448480
289.444 1.456169
253.728 1.465981
228.872 1.476360
214.506 1.484561
206.266 1.490317
194.227 1.500597
184.950 1.510557

Accuracy of measurement
780.237nm~365.119nm ±1×10-6
334.244nm~206.266nm ±3×10-6
194.227nm, 184.950nm ±5×10-6

Laser Durability

Transmittance is nearly unchanged even after applying an ArF excimer laser.

Irradiation conditions
30mJ/cm2 13ns(FWHM)
2×105 shots

Sellmeier’s Dispersion Formula

n2-1=A1λ2/(λ2-B1)+A2λ2/(λ2-B2)+A3λ2/(λ2-B3)

A1
6.254288046×10-1
A2
4.132684951×10-1
A3
3.409193892
B1
2.813183822×10-3
B2
1.066206606×10-2
B3
1.065596428×103

22℃, 1013.25hPa, in nitrogen

Visible/Infrared grade