Characterization of the Ag/YBa2Cu3O7−x contact in thin films
- 15 December 1990
- journal article
- research article
- Published by AIP Publishing in Journal of Applied Physics
- Vol. 68 (12) , 6336-6340
- https://doi.org/10.1063/1.346878
Abstract
Silver (Ag) contacts to very thin superconducting YBa2Cu3O7−x films were prepared by thermal evaporation. The nature of the Ag/YBa2Cu3O7−x contact during thermal treatment was in situ investigated by a combination of three‐ and four‐terminal resistance measurements. The experimental results suggested that the interaction between Ag and the YBa2Cu3O7−x film began at a temperature of around 370 °C. The contact resistance measurement for different films also demonstrated that the contact property was a strong function of the film quality and surface conditions. The lack of reproducibility in forming a low‐resistance contact to very thin YBa2Cu3O7−x films and the high probability of degrading the film quality after thermal treatment of the contact might be due to the excess Ag doping in YBa2Cu3O7−x. Ag island formation, as revealed by scanning electron microscopy after thermal treatment of the contact, is a limitation of Ag for use as a good contact electrode for very thin superconducting films.This publication has 17 references indexed in Scilit:
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