Low temperature crystallized voltage tunable Bi1.5CuxMg1−xNb1.5O7 thin films capable of integration with Au electrode

Bi1.5CuxMg1−xNb1.5O7 (x = 0–0.1) (BCMN) thin films have been fabricated on Au/Ti/SiO2/Si(1 0 0) substrates using a chemical solution spin coating process. Crystallization temperature is reduced and dielectric properties are improved when moderate Mg2+ is substituted by Cu2+ in Bi1.5MgNb1.5O7 thin films. Optimized dielectric properties are obtained in Bi1.5Cu0.075Mg0.925Nb1.5O7 thin films crystallized at a low temperature of 500 °C: dielectric constant ɛr = 173, dielectric loss tan δ = 0.0045 at zero bias field and tunability η = 39%, figure of merit FOM = 86.7 under an applied electric field of ∼1 MV/cm. The combination of low fabrication temperature and favorable dielectric properties of BCMN thin films makes the integration with Au bottom electrode possible.