Electron effective mass and mobility limits in degenerate perovskite stannate BaSn03

摘要

The high room temperature mobility and the electron effective mass in BaSnO_3 are investigated in depth by evaluation of the free carrier absorption observed in infrared spectra for epitaxial films with free electron concentrations from 8.3 × 10~(18) to 7.6α 10~(20) cm~(-3). Both the optical band gap widening by conduction band filling and the carrier scattering mechanisms in the low- and high-doping regimes are consistently described employing parameters solely based on the intrinsic physical properties of BaSnO_3. The results explain the current mobility limits in epitaxial films and demonstrate the potential of BaSnO_3 to outperform established wide-band gap semiconductors also in the moderate doping regime.