Atomic Vapor Depositions of Ti-Ta-O thin films for Metal-Insulator-Metal applications

Abstract Atomic Vapor Deposition technique was applied for the depositions of Ti–Ta–O oxide films for Metal–Insulator–Metal capacitors used in back-end of line for Radio Frequency applications. Composition, crystallinity, thermal stability and electrical properties were studied. Ti–Ta–O films, with the ratio of Ta/Ti ~ 1.5, deposited at 400 °C on TiN electrodes, were amorphous and possessed a dielectric constant of 50 with low voltage linearity coefficients and leakage currents densities as low as 10 − 7  A/cm 2 at 1 V. The films, deposited on Si wafers, were amorphous up to the annealing temperature of 700 °C and crystallized in orthorhombic Ta 2 O 5 phase at higher temperatures.