Rapid deposition of YBCO films by laser CVD and effect of lattice mismatch on their epitaxial growth and critical temperature

a-Axis- and c-axis-oriented YBa2Cu3O7–δ (YBCO) films were grown on (100) SrTiO3 substrate by laser chemical vapour deposition (laser CVD). The effect of lattice mismatch between films and substrates on in-plane and out-of-plane crystallinity and critical temperature (TC) was investigated. The preferred orientation changed from a-axis to c-axis as the deposition temperature increased from 928 to 1049 K. The c-axis-oriented YBCO showed a minimum of full width at half maximum of 0.5° for the ω-scan and 1.0° for the φ-scan. A smaller mismatch between YBCO films and substrates led a higher crystallinity for in-plane and out-of-plane epitaxial growths. A high TC of 90 K was obtained for the c-axis-oriented YBCO films. The deposition rate of the YBCO films was 58–101 μm h−1, approximately 60–1000 times higher than that of conventional CVD.