Velocity saturation in La-doped BaSnO₃ thin films

BaSnO₃, a high mobility perovskite oxide, is an attractive material for oxide-based electronic devices. However, in addition to low-field mobility, high-field transport properties such as the saturation velocity of carriers play a major role in determining the device performance. We report on the experimental measurement of the electron saturation velocity in La-doped BaSnO₃ thin films for a range of doping densities. The predicted saturation velocities based on a simple LO-phonon emission mode, using an effective LO phonon energy of 120 meV show good agreement with the measurements of velocity saturation in La-doped BaSnO₃ films. Density-dependent saturation velocity in the range of 1.8 × 10⁷ cm/s reducing to 2 × 10⁶ cm/s is predicted for δ-doped BaSnO₃ channels with carrier densities ranging from 10¹³ cm⁻² to 2 × 10¹⁴ cm⁻², respectively. These results are expected to aid the informed design of BaSnO₃ as an active material for high-charge density electronic transistors.