Dielectric Properties Of Amorphous Bi-Ti-O Thin Films

We report the unexpectedly excellent dielectric properties of amorphous thin films with compositions in the Bi-Ti-O system. Films were deposited by RF magnetron reactive co-sputtering. In the composition range of 0.5 < x < 0.7, amorphous Bi1-xTixOy exhibits excellent dielectric properties, with a high dielectric constant, epsilon(r) similar to 53, and a dissipation factor as low as tan delta = 0.007. The corresponding maximum breakdown field reaches similar to 1.6 MV/cm, yielding a maximum stored charge per unit area of up to 8 mu C/cm(2). This work demonstrates the potential of amorphous Bi-Ti-O as a high-performance thin-film dielectric material that is compatible with high-performance integrated circuits.