The dielectric constant and loss of the vacuum annealed SFO sample were observed to decrease with decreasing temperature while maintaining a similar frequency-dependent profile, as shown in Fig. 3a. The temperature dependence of the leakage current at the Au/SFO interface, shown in Fig. 3b, follows an exponential behavior with increasing temperature, which indicates a good fit to the thermionic emission model. An effective thermal barrier height, , is extracted from the Schottky equation by using the relationship between ln(J/T2) vs. 1/T at a given E, which is presented in Fig. 3c3338. By then extrapolating from the linear trend of vs. to zero electric field, the intrinsic thermal barrier height, , was calculated with a value of 225 meV for the Au/SFO interface.