Significant discrepancies between these calculations and the standard method, which uses less accurate atomic physics, have been uncovered. The effects of electron density and metastable states have been found to be important. The codes have been used to study several plasmas of commercial interest. One project involves the production of extreme ultraviolet radiation for lithography applications. Relativistic electron beams are injected into a slightly ionized gas.
Energy is transfered from the beam electrons to the plasma electrons which become very hot.
The hot electrons then ionize and excite the surrounding gas atoms to produce the desired radiation. The kinetics codes have been used to predict the output spectrum. In addition, the capability to provide the simultaneous solution of level populations and the free-electron energy distribution is being implemented for this project. Here an electrical discharge is used to excite a gas and produce radiation which is used to drive a display panel. Since the computer simulations are very time consuming the calculated atomic data must be reduced to a model containing only a few atomic states.