Strontium Stannate as an Ultra-Wide Bandgap Semiconductor

The development of superior ultra-wide bandgap (UWBG) semiconductors is crucial for next-generation high-power devices. This talk establishes SrSnO₃ (SSO) as an outstanding UWBG semiconductor. We show SSO thin-film growth with controlled doping and present detailed transport measurements supplemented by first-principles calculations of e-ph interactions and charge transport. We discuss details of the MBE growth, strain relaxation and electronic transport properties as a function of temperature, chemical doping and strain. Our results shed light on the transport behavior and mobility-limiting mechanisms in SSO, and demonstrate that Nd-doped SSO films achieve the best of both worlds – carrier densities as high as 2 × 10²⁰ cm^-3 together with a high room temperature mobility of ~70 cm²V^-1s^-1. These figures of merit place perovskite oxides, for the first time, on par with well-established UWBG semiconductors.