Time, temperature, and oxygen partial pressure-dependent surface reconstructions on SrTiO3(1 1 1): A systematic study of oxygen-rich conditions

The formation of surface reconstructions on the (1 1 1) surface of SrTiO3 following Ar+ ion bombardment and annealing in oxygen-rich (0.2 ⩽ pO2 ⩽ 1.0) environments is systematically investigated using transmission electron microscopy imaging and diffraction. A series of air stable and highly reproducible reconstructions are observed whose periodicity depends on the combination of annealing time, temperature, and oxygen partial pressure. Approximate phase maps can be constructed for each annealing time investigated, and these reveal that for short annealing times (0.5 h) the periodicity of the observed reconstruction is a primarily function of the partial pressure of oxygen in the annealing environment while for long annealing times (10 h) the observed periodicity is primarily a function of the annealing temperature. For intermediate annealing times (5 h), three coexisting reconstructions are observed to exist on a single specimen.