Synthesis of YBa sub 2 SbO sub 6 : a Possible New Substrate for YBa sub 2 Cu sub 3 O sub 7--sp(w) Thin Films

The addition of Sb sub 2 O sub 3 to YBa sub 2 Cu sub 3 O sub 7--sp(w) resulted in the formation of a second phase during high-temperature sintering at 950 deg C. This phase is identified as YBa sub 2 SbO sub 6 , having a cubic structure with a lattice constant a = 8.403 A. This compound has been synthesized as a single-phase material by solid-state reaction for the first time. Sintering conditions and its dielectric properties are discussed. No chemical reaction was observed between YBa sub 2 Cu sub 3 O sub 7--sp(w) and YBa sub 2 SbO sub 6 even after annealing a 1:1 molar mixture at 950 deg C for 15 h. Addition of YBa sub 2 SbO sub 6 up to 10 wt.% to YBa sub 2 Cu sub 3 O sub 7--sp(w) did not have any detrimental effect on the superconducting properties of YBa sub 2 Cu sub 3 O sub 7--sp(w) . YBa sub 2 SbO sub 6 is proposed as an ideal substrate material for the deposition of YBa sub 2 Cu sub 3 O sub 7 thin films.