Growth of Y-Ba-Cu-O Thin Films on Al2O3/Si by MOCVD

Abstract

Superconducting thin films of YBa2Cu3O7-x (YBCO) were deposited on Si substrate with AI2O3 buffer layer and LiNbO3 single crystal substrates by in-situ metalorganic chemical vapor deposition (MOCVD) technique. A resistive heated vertical cold-wall reaction chamber using N2O gas as an oxidizer was successful to deposit thin films of YBCO and epitaxial AI2O3 buffer layer without post annealing. A buffer layer of MOCVD grown Al2O3 film on (100) Si is found to be γ phase Al2O3 hetero-epitaxial film from the x-ray diffraction analysis. As-deposited YBCO film on Al2O3/Si substrate at a substrate temperature of 800 ∼ 850° C showed superconducting behavior at Tc, zero = 58 K. YBCO films on Z-cut LiNbO3 single crystal substrate by in-situ MOCVD growth also showed Tc, zero = 85 K. Auger electron spectroscopy (AES) for depth profile analysis is discussed.