A laser energy deposition model has been incorporated into the MHRDR-EUVL magnetohydrodynamic (MHD) model of EUV sources for microlithography. The model includes inverse-bremsstrahlung absorption, resonance absorption, and reflection of laser radiation from the plasma critical surface. The plasma evolution is simulated in parallel with the MHRDR-EUVL (Magneto-Hydro-Radiative-Dynamic-Research) 2D, three-temperature, MHD computer code. Convenient user-options include simple specification of the full width at half maximum (FWHM) of typical laser profiles, such as Gaussian profiles in space and time. The new laser deposition capability will allow MHRDR-EUVL to calculate the evolution of magnetized laser-produced plasmas. Magnetic fields can reduce the loss of plasma energy caused by plasma expansion and thermal conductivity.
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