The effect of susceptor inclination angle on the quality of superconducting YBCO thin films prepared by a photo-assisted MOCVD system

Superconducting YBa2Cu3O7−x thin films were deposited on LaAlO3 (1 0 0) substrates by a photo-assisted metal-organic chemical vapor deposition (MOCVD) technique. In our experiment, growth temperature, chamber pressure and growth time were all fixed; the only process variable was the susceptor inclination angle (Φ) between the axis of gas inlet and the susceptor surface. It was found that the growth rate of YBCO films increases monotonically as Φ increases, whereas the superconducting critical current density (Jc) has a maximum (1.2 × 106 A/cm2) near Φ = 22.5°. The experimental results were found to be well correlated with the three-dimensional simulations of gas flow inside the MOCVD reactor, with Φ being the only process variable.