Polarity control and growth mode of InN on yttria-stabilized zirconia (111) surfaces

We have found that polarity of epitaxial InN layers has been controlled by choice of a capping material during high‐temperature annealing of yttria‐stabilized zirconia (YSZ) (111) substrates in air. Angle‐resolved X‐ray photoelectron spectroscopy has revealed that the amount of segregation of Y atoms to the YSZ surface depended on the capping material of the substrates. In‐polar and N‐polar InN have been reproducibly grown on Y‐segregated and Y‐segregation‐free YSZ surfaces, respectively. We have also found that the growth of the first monolayer (ML) of N‐polar InN proceeds in a step‐flow mode which then switches to layer‐by‐layer mode after the coverage by 1‐ML‐thick InN.