Measurement of temporal behavior of electron density in a discharge-pumped ArF excimer laser

Time-resolved number densities of electrons in a discharge-pumped ArF excimer laser are measured by an interferometric method. The peak electron density is 6.7 x 10(15) cm(-3) at a total gas pressure of 2.5 atom, a gas mixture ratio tio of F-2-Ar-He = 0.2-10.0-89.8, and a charging voltage of 24 kV for a 68-nF storage capacitor bank. The dependences of the electron density and laser output power on the Ar and F-2 fractions in Ar-F-2-He mixture and on the Ne-He mixing ratio in Ar-F-2-He-Ne mixture are investigated, and the effects of Ar-F-2-He-Ne mixing ratio on the ArF laser discharge are discussed. The experimental data of the peak electron density are also compared with the results of a computer simulation. A good agreement between them was obtained by considering the bet that the actual discharge volume occupied only part of the electrode width.