Thursday, 27 September 2018 at 3:15 pm
McCullough, First Floor Auditorium, Room #115
Host: Yuri Suzki
University of Minnesota, Minneapolis
Towards Development of Oxide Heterostructures with High Room-Temperature Mobility
Doped-BaSnO3 and SrSnO3 are promising materials for high-power electronics owing to wide bandgap (~3 – 4.5 eV), high conductivity with reasonably high electron mobility, and excellent thermal stability. There are however several materials challenges which limit their device performance. In this talk, I will review these challenges in the context of molecular beam epitaxy (MBE) for the growth of defect-managed oxide thin films and heterostructures. I will present our group’s effort to address these challenges using a new radical-based hybrid MBE technique. Using Stannate (BaSnO3 and SrSnO3) as a model material system, I will present a comprehensive growth, and electronic transport study of La-doped BaSnO3 and SrSnO3 yielding a record-high conductivity in optically transparent, doped-BaSnO3 films through defect management. I will present the important role of defects such as dislocations, and non-stoichiometry on electronic transport in addition to discussing different scattering mechanisms that limit the room temperature electron mobility in La-doped BaSnO3. Finally, I will present pathways to enhance electron mobilities towards high room-temperature mobility oxide heterostructures using band structure engineering.
Work supported by the NSF, and AFOSR YIP Program.