Study of optical emission of the laser generated plasma of a Ag/YBa/sub 2/Cu/sub 3/O/sub 7-/spl delta// target: and its consequences to oxide film growth

Summary form only given, as follows. In situ diagnostics of pulsed laser ablated plasmas have been used to characterize thin film growth environments. It is important to correlate the plasma conditions with film properties such as stoichiometry and crystallinity. Optical emission spectroscopy has proved to be a very useful and robust technique for plasma diagnostics. We have carried out optical spectroscopy of the laser plume of a Ag/YBa/sub 2/Cu/sub 3/O/sub 7-/spl delta// composite target under different oxygen base pressures generated by a 248 nm KrF pulsed eximer laser with a pulse width of 20 ns. The results of the optical spectroscopy have been compared with that from a pure target of YBa/sub 2/Cu/sub 3/O/sub 7-/spl delta// (YBCO). The YBCO films were deposited on MgO(100) substrates at temperatures between 600-700/spl deg/C. The film composition and properties were analyzed using Auger spectroscopy, transmission electron microscopy, X-ray diffraction and electrical transport measurements. The films grown from Ag/Ba/sub 2/Cu/sub 3/O/sub 7-/spl delta// have demonstrated enhanced crystallinity and superconducting properties though Ag concentrations in the films were low and decreased further with increasing deposition temperatures. Results of optical emission spectroscopy indicates that the formation of silver oxide (AgO) species in the plasma is the key to enhanced oxygenation of the superconducting YBCO films, which leads to the possibility of lowering processing temperatures for the growth of oxide thin films.