Ti- and Sr-rich surfaces of SrTiO3 studied by grazing incidence X-ray diffraction

The structure of SrTiO3 (100) (STO) single crystal surfaces has been investigated by grazing incidence x-ray diffraction. The authors found that chemically etched STO is composed similar to 75% of an ideal TiO2 surface layer and similar to 25% of SrO and it is very stable when annealed in ultrahigh vacuum or in O-2 at high temperatures. A monolayer of SrO, epitaxially grown by pulsed laser deposition, is found to cover only a fraction of the TiO2 layers and exhibits a 2x2 reconstruction with strong structural changes after annealing in conditions typically used for the deposition of oxides. (c) 2007 American Institute of Physics.