Tunable, low loss Bi_(1.5)Zn_(1.0)Nb_(1.5)O_7/Ba_(0.6)Sr_(0.4)TiO_3/Bi_(1.5)Zn_(1.0)Nb_(1.5)O_7 sandwich films

摘要

Bi_(1.5)Zn_(1.0)Nb_(1.5)O_7/Ba_(0.6)Sr_(0.4)TiO_3/Bi_(1.5)Zn_(1.0)Nb_(1.5)O_7 (BZN/BST/BZN) sandwich films were deposited by radio frequency magnetron sputtering. The relative permittivity and dielectric loss of the sandwich films were measured using planar Pt/BZN/BST/BZN/Pt/Ti/SiO_2/Si capacitor structures. The sandwich films with thickness of about 280 nm exhibited relative permittivity around 206-247 and dielectric loss tangent (tan δ) less than 0.008 at 1 MHz. Films annealed at 750℃ had an ～11% relative tunability of the permittivity at a maximum applied bias field of 0.77 MV/cm. The sandwich films are not ferroelectric at room temperature.