Leakage current of Pt/(Ba0.7Sr0.3)TiO3 (BST)/YBa2Cu3O7-delta capacitors on a (001) SrTiO3 substrate was studied. By modeling a low-dielectric constant layer, a so-called dead layer, between the Pt/BST interface as a parasitic capacitor in series with the bulk layer capacitor, the leakage current of Pt/BST interface was well analyzed based on the modified Schottky emission equation. Furthermore, a two-step schematic energy band diagram is proposed to explain the carrier transport through the Pt/BST interface. (C) 2005 American Institute of Physics.