STUDY OF ION ACTIVATION IN THE IN-SITU LOW-TEMPERATURE LASER DEPOSITION OF SUPERCONDUCTING YBA2CU3O7-DELTA FILMS

The presence of a pulsed discharge during the reactive deposition of high T(C) thin films allows the lowering of substrate temperatures to approximately 475-degrees-C for in situ superconducting film deposition. We present the first ion probe analysis to study the role of this pulsed discharge on the excimer laser ablated YBa2Cu3O7-delta Plume. The ionic enhancement in the laser-ablated plume, during reactive deposition in the presence of a positively biased ring electrode, is studied both in terms of its extent and temporal characteristics. A significant increase in the forward-directed incidence of oxygen ions on the depositing substrate, following in the wake of the highly directional plume, is demonstrated. The dependence of this ionic enhancement on ambient oxygen pressure and the bias voltage on the ring electrode is discussed.