Velocity Saturation in La-doped BaSnO3 Thin Films

TL;DR

This study measures and models the high-field electron saturation velocity in La-doped BaSnO3 thin films, providing insights crucial for designing high-performance oxide electronic devices.

Contribution

It experimentally determines the electron saturation velocity in La-doped BaSnO3 and validates a simple LO-phonon emission model for predicting velocity saturation.

Findings

Measured saturation velocities align with model predictions.

Saturation velocity decreases with increasing doping density.

Density-dependent saturation velocities range from 1.6x10^7 to 2x10^6 cm/s.

Abstract

BaSnO_{3}, 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 device performance. We report on the experimental measurement of electron saturation velocity in La-doped BaSnO_{3} thin films for a range of doping densities. Predicted saturation velocities based on a simple LO-phonon emission model using an effective LO phonon energy of 120 meV show good agreement with measurements of velocity saturation in La-doped BaSnO_{3} films.. Density-dependent saturation velocity in the range of 1.6x10^{7} cm/s reducing to 2x10^{6} cm/s is predicted for {\delta}-doped BaSnO3 channels with carrier densities ranging from 10^{13} cm^{-2} to 2x10^{14} cm^{-2} respectively. These results are expected to aid the informed design of BaSnO3 as the active material for high-charge density electronic transistors.