Ultrathin Y2O3(111) films on Pt(111) substrates

► Yttria is deposited on Pt(111) by reactive physical vapor deposition. ► Ordered Y2O3(111)-1 × 1 surface is obtained by post-growth annealing. ► Thin film yttria on Pt(111) can be used as a model system for surface science studies of yttria.