Growth of highly conducting delafossite thin films

Jong Mok Ok

ABO delafossite oxides have attracted recent attention because they have a natural heterostructure of hexagonal A and BO layers that provide a diverse set of physical properties. In the delafossite oxides, A-site electrons occupy a band near the Fermi level with steep band dispersion, while B-site electrons are strongly correlated and have Mott-insulating characteristics. The diverse combination of A and B atoms provides a wide range of fascinating properties. The most notable properties found in delafossites include the highest figure of merit among the p-type transparent conducting oxides and extremely high conductivity. Layer-by-layer growth of delafossites not only provides a route to utilize their diverse properties in future devices and applications, but also enables the design of artificial delafossite heterostructures with which new physics and chemistry can be realized. Despite the efforts to grow delafossite thin films thus far, many challenges still must be solved to enable the growth of high-quality thin films.