Scalable Synthesis of the Transparent Conductive Oxide SrVO₃

The correlated metal SrVO₃ is an attractive earth-abundant transparent conducting oxide (TCO), a critical component of many optoelectronic and renewable energy devices. A key challenge is to synthesize films with low resistivity, due to the prevalence of defects that cause electron scattering. In addition to the material's promise as a TCO, its interesting correlated-electron physics is often obscured by a high defect concentration, which inhibits its further development into new types of devices. A route to synthesize low-defect SrVO₃ films by scalable, industry-compatible molecular beam epitaxy (MBE) is demonstrated. The resulting films consistently exhibit a residual resistivity ratio in the excess of 10 and room temperature resistivity as low as 32 µΩ cm, an indication of their high quality and potential for applications. Analysis of the structural and electronic properties of SrVO₃ films provides insights that are applicable to other conductive oxides, and highlights a route for further improvement in their quality and low temperature performance. MBE is the only growth method that allows atomically abrupt epitaxial interfaces between oxides and semiconductors such as Si and GaAs. Such interfaces are essential for efficient charge transport that is at the heart of the performance of most optoelectronic and solar devices.