Krypton fluoride laser
Template:Current-SCOTW A krypton fluoride laser (KrF laser) absorbs energy from a source and causes the krypton gas to react with the fluorine gas, producing krypton fluoride, which is an unstable compound.
- 2Kr (g) + F2 (g) electron energy→ 2KrF (g)
When the supplied energy is stopped, the compound will decompose and the excess chemical energy stored in the compound will release in the form of strongly synchronized radiation.
- 2KrF (g) → 2Kr (g) + F2 (g) + energy
The result is an excimer laser that radiates energy at 248 nm, which lies in the near ultraviolet portion of the spectrum. The KrF laser has been of interest in the fusion energy research community due to the high beam uniformity, short wavelength, and the ability to modify the spot size to track an imploding pellet.
The Laser Plasma Branch of the Naval Research Laboratory completed a KrF laser called Nike that can produce about 4.5 × 103 Joules of UV energy output in a 4 nanosecond pulse. This laser is being used in laser confinement experiments.
The KrF laser is also used in laser lithography, where the short wavelength is desireable for etching very small features. However it will likely be replaced for this purpose by the argon flouride laser, which has a 193 nm wavelength. Pulse widths of KrF lasers in commercial applications is typically 20-30 nanoseconds.
References
- J. Sethian, M. Friedman, M. Myers, S. Obenschain, R, Lehmberg, J. Giuliani, P. Kepple, F. Hegeler, S. Swanekamp, D. Weidenheimer, "Krypton Flouride Laser Development for Inertial Fusion Energy".
- M. C. Myers, J. D. Sethian, J. L. Giuliani, R. Lehmberg, P. Kepple, M. F. Wolford, F. Hegeler, M. Friedman, T. C. Jones, S. B. Swanekamp, D. Weidenheimer and D. Rose, "Repetitively pulsed, high energy KrF lasers for inertial fusion energy", 2004, Nuclear Fusion, 44.
- J. Goldhar, K. S. Jancaitis, J. R. Murray, L. G. Schlitt, "An 850 J, 150 ns narrow-band krypton fluoride laser", 1984, 13th Intern. Conf. on Quantum Electron.