Time-resolved emission spectra following the 193-nm photoablation of CuO, BaO sub 2 , Y sub 2 O sub 3 , and YBa sub 2 Cu sub 3 O sub 7 minus x in vacuum and oxygen

Gated diode array spectra were taken after the photoablation of CuO, BaO{sub 2}, Y{sub 2}O{sub 3}, and YBa{sub 2}Cu{sub 3}O{sub 7} in vacuum and oxygen. An ArF excimer laser (193 nm) was used for photoablation. The spectra were resolved on a microsecond time scale. Emission from ions, atoms, and molecular oxides are observed and identified. Observations in the first microsecond represent phenomena produced in the primary ablation process. This emission is due primarily to high-energy collisions of ejected atoms and ions. Later time observations reveal that excited metal oxides are formed from reactive collisions of barium and yttrium atoms with the background oxygen, when present. Such species may be responsible for improved film quality in the presence of oxygen.